diff --git a/include/config.h b/include/config.h
index ac3b6c15e..5509d5356 100644
--- a/include/config.h
+++ b/include/config.h
@@ -150,10 +150,11 @@
  *		If SYSCF is defined, the following configuration info is
  *		available in a global config space, with the compiled-in
  *		entries as defaults:
- *		WIZARD		( a value of * allows anyone to be wizard)
+ *		WIZARDS		( a value of * allows anyone to be wizard)
  *		MAXPLAYERS	(see MAX_NR_OF_PLAYERS above and nethack.sh)
  *		SUPPORT		(how to get local support)(no default)
  *		RECOVER		(how to recover a game at your site)(no default)
+ *		SHELLERS	(who can use !, syntax as WIZARDS)
  *
  *		The following options select how the config space is stored:
  *		SYSCF_FILE	in the named file
diff --git a/include/extern.h b/include/extern.h
index 9ace6362b..96d78078a 100644
--- a/include/extern.h
+++ b/include/extern.h
@@ -2322,6 +2322,7 @@ E void NDECL(port_help);
 # endif
 E void FDECL(sethanguphandler, (void (*)(int)));
 E boolean NDECL(authorize_wizard_mode);
+E boolean FDECL(check_user_string, (char *));
 #endif /* UNIX */
 
 /* ### unixtty.c ### */
diff --git a/include/sys.h b/include/sys.h
index 7ec3db55b..587fb01bb 100644
--- a/include/sys.h
+++ b/include/sys.h
@@ -13,6 +13,7 @@ struct sysopt {
 	char *support;	/* local support contact */
 	char *recover;	/* how to run recover - may be overridden by win port */
 	char *wizards;
+	char *shellers;	/* like wizards, for ! command (-DSHELL) */
 	int   maxplayers;
 };
 E struct sysopt sysopt;
diff --git a/include/unixconf.h b/include/unixconf.h
index 79c14fa87..d322e4aab 100644
--- a/include/unixconf.h
+++ b/include/unixconf.h
@@ -279,7 +279,9 @@
 #endif
 #define tgetch getchar
 
-#define SHELL		/* do not delete the '!' command */
+#ifndef NOSHELL
+# define SHELL		/* do not delete the '!' command */
+#endif
 
 #include "system.h"
 
diff --git a/src/files.c b/src/files.c
index cb10c0d40..75495c3f8 100644
--- a/src/files.c
+++ b/src/files.c
@@ -2066,10 +2066,14 @@ int		src;
 	} else if (match_varname(buf, "CATNAME", 3)) {
 	    (void) strncpy(catname, bufp, PL_PSIZ-1);
 #ifdef SYSCF
-	} else if ( (src==SET_IN_SYS) && match_varname(buf, "WIZARDS", 6)) {
+	} else if ( (src==SET_IN_SYS) && match_varname(buf, "WIZARDS", 7)) {
 	    if(sysopt.wizards) free(sysopt.wizards);
 	    sysopt.wizards = alloc(strlen(bufp));
 	    (void) strcpy(sysopt.wizards, bufp);
+	} else if ( (src==SET_IN_SYS) && match_varname(buf, "SHELLERS", 8)) {
+	    if(sysopt.shellers) free(sysopt.shellers);
+	    sysopt.shellers = alloc(strlen(bufp));
+	    (void) strcpy(sysopt.shellers, bufp);
 	} else if ( (src==SET_IN_SYS) && match_varname(buf, "SUPPORT", 7)) {
 	    if(sysopt.support) free(sysopt.support);
 	    sysopt.support = alloc(strlen(bufp));
diff --git a/src/sys.c b/src/sys.c
index 895c73438..2575d6624 100644
--- a/src/sys.c
+++ b/src/sys.c
@@ -14,6 +14,7 @@ sys_early_init(){
 	/* replace use of WIZARD vs WIZARD_NAME vs KR1ED, by filling this in */
 #endif
 	sysopt.wizards = NULL;
+	sysopt.shellers = NULL;
 	sysopt.maxplayers = 0;	/* XXX eventually replace MAX_NR_OF_PLAYERS */
 }
 
diff --git a/sys/unix/Makefile.top b/sys/unix/Makefile.top
index 742380035..3cf757323 100644
--- a/sys/unix/Makefile.top
+++ b/sys/unix/Makefile.top
@@ -38,7 +38,7 @@ DIRPERM  = 0755
 # instructions)
 #HACKDIR  = $(PREFIX)/games/lib/$(GAME)dir
 VARDIR  = $(HACKDIR)
-SHELLDIR = $(PREFIX)/games
+#SHELLDIR = $(PREFIX)/games
 
 # per discussion in Install.X11 and Install.Qt
 #VARDATND = 
@@ -245,7 +245,7 @@ install: rootcheck $(GAME) recover $(VARDAT) dungeon spec_levs
 	-mkdir -p $(SHELLDIR)
 	-rm -rf $(HACKDIR) $(VARDIR)
 	-mkdir -p $(HACKDIR) $(VARDIR) $(VARDIR)/save
-	-rmdir ./-p
+	if test -d ./-p; then rmdir ./-p; fi
 	-$(CHOWN) $(GAMEUID) $(HACKDIR) $(VARDIR) $(VARDIR)/save
 	$(CHGRP) $(GAMEGRP) $(HACKDIR) $(VARDIR) $(VARDIR)/save
 # order counts here:
diff --git a/sys/unix/hints/linux b/sys/unix/hints/linux
index 46971c6e6..099c3d662 100644
--- a/sys/unix/hints/linux
+++ b/sys/unix/hints/linux
@@ -9,6 +9,7 @@
 
 
 HACKDIR=$(PREFIX)/games/lib/$(GAME)dir
+SHELLDIR = $(PREFIX)/games
 #PREFIX=/usr
 PREFIX=$(wildcard ~)/nh/install
 
diff --git a/sys/unix/hints/linux-x11 b/sys/unix/hints/linux-x11
index 84adc1cf2..baa316e68 100644
--- a/sys/unix/hints/linux-x11
+++ b/sys/unix/hints/linux-x11
@@ -9,6 +9,7 @@
 
 
 HACKDIR=$(PREFIX)/games/lib/$(GAME)dir
+SHELLDIR = $(PREFIX)/games
 #PREFIX=/usr
 PREFIX=$(wildcard ~)/nh/install
 
diff --git a/sys/unix/hints/macosx.sh b/sys/unix/hints/macosx.sh
index a40f9d99e..4eb9e20a9 100755
--- a/sys/unix/hints/macosx.sh
+++ b/sys/unix/hints/macosx.sh
@@ -1,22 +1,28 @@
 #!/bin/sh
-#      SCCS Id: @(#)macosx-mu.sh 3.5     2007/12/12
+#      SCCS Id: @(#)macosx.sh 3.5     2007/12/12
 # Copyright (c) Kenneth Lorber, Kensington, Maryland, 2007.
 # NetHack may be freely redistributed.  See license for details.
 #
 # hints helper script for macosx
-# DO NOT invoke directly
+# DO NOT invoke directly.
+
+# Works for 10.4 and 10.5.  (The 10.5 support might work for 10.4 but keep
+# both versions in case we need to support earlier versions.)
 
 cmd=$1
 
+echo "macosx: $*"
+
 case "x$cmd" in
 xuser)
+		# fail unless user exists (good through 10.4)
 	user=$2
 	gotuser=`niutil -readval . /users/$user name 0 2>/dev/null`
 	[ -z $gotuser ] && (echo "User $user does not exist."
 		exit 1;
 	)
-	exit 0
 	;;
+
 #name: dummy1
 #_writers_passwd: dummy1
 #_writers_tim_password: dummy1
@@ -35,14 +41,16 @@ xuser)
 #authentication_authority: ;ShadowHash;
 #realname: dummyname1
 #generateduid: F6D4991C-BDF5-481F-A407-D84C6A2D0E2A
+
 xgroup)
+		# fail unless group exists (good through 10.4)
 	group=$2
 	gotgrp=`niutil -readval . /groups/$group name 0 2>/dev/null`
 	[ -z $gotgrp ] && ( echo "Group $group does not exist."
 		exit 1
 	)
-	exit 0
 	;;
+
 #niutil -read . /groups/bin name 0
 #name: bin
 #gid: 7
@@ -51,7 +59,92 @@ xgroup)
 #smb_sid: S-1-5-21-107
 #realname: Binary
 
+xuser2)
+		# fail unless user exists (required as of 10.5)
+	user=$2
+	if( dscl localhost -read /Search/Users/$user 1>/dev/null 2>&1 );
+	then
+		true;
+	else
+		echo "User $user does not exist.";
+		exit 1;
+	fi
+	;;
+
+xgroup2)
+		# if group does not exist, create it (required as of 10.5)
+	group=$2
+	[ -z $group ] && ( echo "No group specified."
+		exit 1
+	)
+	if( dscl localhost -read /Search/Groups/$group 1>/dev/null 2>&1 );
+	then
+		true;
+	else
+		echo "Group $group does not exist - creating.";
+		dseditgroup -o create -r "Games Group" -s 3600 $group
+		if( dscl localhost -read /Search/Groups/$group 1>/dev/null 2>&1 );
+		then
+			true;
+		else
+			echo "Unable to create group $group."
+			exit 1
+		fi
+	fi
+	;;
+
+#% dscl localhost -read /Search/Groups/wheel
+# AppleMetaNodeLocation: /Local/Default
+# GeneratedUID: ABCDEFAB-CDEF-ABCD-EFAB-CDEF00000000
+# GroupMembership: root
+# Password: *
+# PrimaryGroupID: 0
+# RealName:
+#  System Group
+# RecordName: wheel
+# RecordType: dsRecTypeStandard:Groups
+# SMBSID: S-1-5-21-100
+
 *)      echo "Unknown command $cmd"
 	exit 1
         ;;
 esac
+
+# dscl localhost -read /Search/Users/games
+# dsAttrTypeNative:_writers_hint: games
+# dsAttrTypeNative:_writers_jpegphoto: games
+# dsAttrTypeNative:_writers_LinkedIdentity: games
+# dsAttrTypeNative:_writers_passwd: games
+# dsAttrTypeNative:_writers_picture: games
+# dsAttrTypeNative:_writers_realname: games
+# dsAttrTypeNative:_writers_UserCertificate: games
+# AppleMetaNodeLocation: /Local/Default
+# AuthenticationAuthority: ;ShadowHash; ;Kerberosv5;;games@LKDC:SHA1.3F695B215C78511043D9787CA51DE92E6494A021;LKDC:SHA1.3F695B215C78511043D9787CA51DE92E6494A021;
+# AuthenticationHint: games
+# GeneratedUID: A727EFB1-D6AA-4FE2-8524-0E154890E9A9
+# NFSHomeDirectory: /Users/games
+# Password: ********
+# Picture:
+#  /Library/User Pictures/Flowers/Sunflower.tif
+# PrimaryGroupID: 20
+# RealName: games
+# RecordName: games
+# RecordType: dsRecTypeStandard:Users
+# UniqueID: 505
+# UserShell: /bin/bash
+
+# see also: http://developer.apple.com/documentation/Porting/Conceptual/PortingUnix/additionalfeatures/chapter_10_section_9.html
+
+# another mess: 10.4 creates a group for every user, 10.5 dumps you into staff.
+# so I think we need to explicitly create group games in both (if it doesn't
+# exist) and use owner bin (nope that fails since everything seems to be owned
+# by root.  Do we want that?  How about just creating user games as well?)
+
+# [Hermes:sys/unix/hints] keni% dscl localhost -read /Search/Users/games9
+# <dscl_cmd> DS Error: -14136 (eDSRecordNotFound)
+# [Hermes:sys/unix/hints] keni% dscl localhost -read /Search/Users/games9 >/dev/null
+# <dscl_cmd> DS Error: -14136 (eDSRecordNotFound)
+# [Hermes:sys/unix/hints] keni% dscl localhost -read /Search/Users/games > /dev/null
+# status is good: 0 or 56
+
+# file:///Developer/Documentation/DocSets/com.apple.ADC_Reference_Library.CoreReference.docset/Contents/Resources/Documents/releasenotes/MacOSXServer/RN-DirectoryServices/index.html
diff --git a/sys/unix/hints/macosx10.5 b/sys/unix/hints/macosx10.5
new file mode 100644
index 000000000..9a864b6e0
--- /dev/null
+++ b/sys/unix/hints/macosx10.5
@@ -0,0 +1,152 @@
+#
+#      SCCS Id: @(#)macosx 3.5     2007/12/12
+# Copyright (c) Kenneth Lorber, Kensington, Maryland, 2007.
+# NetHack may be freely redistributed.  See license for details.
+#
+# Mac OS X (Darwin) hints file
+# This is for Mac OS X 10.5.3 (Darwin 9.3).  If this doesn't work for some
+# other version of either Darwin or Mac OS X, make a new file for that OS,
+# don't change this one.  And let us know about it.
+# Useful info: http://www.opensource.apple.com/darwinsource/index.html
+
+# This hints file can build several different types of installations.
+# Edit the next section to match the type of build you need.
+
+# 1. Which window system(s) should be included in this binary?
+WANT_WIN_TTY=1
+#WANT_WIN_X11=1
+#WANT_WIN_QT=1
+
+# 1a. What is the default window system?
+WANT_DEFAULT=tty
+#WANT_DEFAULT=x11
+#WANT_DEFAULT=qt
+
+# 1b. If you set WANT_WIN_QT, you need to
+#  A) set QTDIR either here or in the environment to point to the Qt2 or Qt3
+#     library installation root.  (Qt4 will not work; Qt3 does not presently
+#     compile under Leopard (MacOSX 10.5) out-of-the-box.)
+#  B) set XPMLIB to point to the Xpm library
+ifdef WANT_WIN_QT
+QTDIR=/Developer/Qt
+LIBXPM= -L/Developer/SDKs/MacOSX10.3.9.sdk/usr/X11R6/lib -lXpm
+endif
+
+# 2. Is this a build for a binary that will be shared among different users
+#    or will it be private to you?
+#    If it is shared:
+#	- it will be owned by the user and group listed
+#	- if the user does not exist, you MUST create it before installing
+#	  NetHack
+#	- if the group does not exist, it will be created.
+#	  NB: if the group already exists and is being used for something
+#	   besides games, you probably want to specify a new group instead
+#	  NB: the group will be created locally; if your computer is centrally
+#	   administered this may not be what you (or your admin) want.
+#	   Consider a non-shared install (WANT_SHARE_INSTALL=0) instead.
+#	- 'make install' must be run as "sudo make install"    
+WANT_SHARE_INSTALL=1
+GAMEUID  = root
+GAMEGRP  = games
+
+#CC=gcc -W -Wimplicit -Wreturn-type -Wunused -Wformat -Wswitch -Wshadow -Wcast-qual -Wwrite-strings -DGCC_WARN
+CC=gcc -Wall -Wextra -Wno-missing-field-initializers -Wimplicit -Wreturn-type -Wunused -Wformat -Wswitch -Wshadow -Wwrite-strings -DGCC_WARN -ansi
+
+#
+# You shouldn't need to change anything below here.
+#
+
+# XXX -g vs -O should go here, -I../include goes in the makefile
+CFLAGS=-g -I../include
+CFLAGS+=-DNOCLIPPING -DNOMAIL -DNOTPARMDECL -DHACKDIR=\"$(HACKDIR)\"
+CFLAGS+= -DDEFAULT_WINDOW_SYS=\"$(WANT_DEFAULT)\"
+
+ifdef WANT_WIN_TTY
+WINSRC = $(WINTTYSRC)
+WINOBJ = $(WINTTYOBJ)
+WINLIB = $(WINTTYLIB)
+WINTTYLIB=-lncurses
+else
+CFLAGS += -DNOTTYGRAPHICS
+endif
+
+ifdef WANT_WIN_X11
+WINSRC += $(WINX11SRC)
+WINOBJ += $(WINX11OBJ)
+WINLIB += $(WINX11LIB)
+LFLAGS=-L/usr/X11R6/lib
+VARDATND = x11tiles NetHack.ad pet_mark.xbm
+POSTINSTALL= bdftopcf win/X11/nh10.bdf > $(HACKDIR)/nh10.pcf; (cd $(HACKDIR); mkfontdir)
+CFLAGS += -DX11_GRAPHICS
+endif
+
+ifdef WANT_WIN_QT
+CFLAGS += -DQT_GRAPHICS -DNOUSER_SOUNDS
+CFLAGS += -isysroot /Developer/SDKs/MacOSX10.4u.sdk -mmacosx-version-min=10.4
+LINK=g++
+WINSRC += $(WINQTSRC)
+WINLIB += $(WINQTLIB) $(LIBXPM)
+WINLIB += -framework Carbon -framework QuickTime -lz -framework OpenGL
+WINLIB += -framework AGL
+ifdef WANT_WIN_X11
+	# prevent duplicate tile.o in WINOBJ
+WINOBJ = $(sort $(WINQTOBJ) $(WINX11OBJ))
+ifdef WANT_WIN_TTY
+WINOBJ += $(WINTTYOBJ)
+endif
+else
+WINOBJ += $(WINQTOBJ)
+endif
+# XXX if /Developer/qt exists and QTDIR not set, use that
+ifndef QTDIR
+$(error QTDIR not defined in the environment or Makefile)
+endif
+# XXX make sure QTDIR points to something reasonable
+else
+LINK=$(CC)
+endif
+
+ifdef WANT_SHARE_INSTALL
+# if $GAMEUID is root, we install into roughly proper Mac locations, otherwise
+# we install into ~/nethackdir
+ifeq ($(GAMEUID),root)
+PREFIX:=/Library/NetHack
+SHELLDIR=/usr/local/bin
+HACKDIR=$(PREFIX)/nethackdir
+else
+PREFIX:=/Users/$(GAMEUID)
+SHELLDIR=$(PREFIX)/bin
+HACKDIR=$(PREFIX)/nethackdir
+endif
+CHOWN=chown
+CHGRP=chgrp
+# We run sgid so the game has access to both HACKDIR and user preferences.
+GAMEPERM = 02755
+VARFILEPERM = 0664
+VARDIRPERM = 0775
+ROOTCHECK= [[ `id -u` == 0 ]] || ( echo "Must run install with sudo."; exit 1)
+# make sure we have group GAMEUID and group GAMEGRP
+PREINSTALL= . sys/unix/hints/macosx.sh user2 $(GAMEUID); . sys/unix/hints/macosx.sh group2 $(GAMEGRP); mkdir $(SHELLDIR); chown $(GAMEUID) $(SHELLDIR)
+POSTINSTALL= touch $(HACKDIR)/sysconf; $(CHOWN) $(GAMEUID) $(HACKDIR)/sysconf; $(CHGRP) $(GAMEGRP) $(HACKDIR)/sysconf; chmod $(VARFILEPERM) $(HACKDIR)/sysconf
+CFLAGS+=-DSYSCF -DSYSCF_FILE=\"$(HACKDIR)/sysconf\" -DSECURE
+else
+PREFIX:=$(wildcard ~)
+SHELLDIR=$(PREFIX)/bin
+HACKDIR=$(PREFIX)/nethackdir
+CHOWN=true
+CHGRP=true
+GAMEPERM = 0700
+VARFILEPERM = 0600
+VARDIRPERM = 0700
+ifdef WANT_WIN_X11
+# XXX install nethack.rc as ~/.nethackrc if no ~/.nethackrc exists
+endif
+endif
+
+
+# ~/Library/Preferences/NetHack Defaults
+# OPTIONS=name:player,number_pad,menustyle:partial,!time,showexp
+# OPTIONS=hilite_pet,toptenwin,msghistory:200,windowtype:Qt
+#
+# Install.Qt mentions a patch for macos - it's not there (it seems to be in the Qt binary
+# package under the docs directory).
diff --git a/sys/unix/unixmain.c b/sys/unix/unixmain.c
index 773cda08f..308c1c35b 100644
--- a/sys/unix/unixmain.c
+++ b/sys/unix/unixmain.c
@@ -42,6 +42,7 @@ extern void NDECL(init_linux_cons);
 
 static void NDECL(wd_message);
 static boolean wiz_error_flag = FALSE;
+static struct passwd *NDECL(get_unix_pw);
 
 int
 main(argc,argv)
@@ -530,40 +531,10 @@ boolean
 authorize_wizard_mode()
 {
 #ifdef WIZARD
-	char *user;
-	int uid;
-	struct passwd *pw = (struct passwd *)0;
-
-	uid = getuid();
-	user = getlogin();
-	if (user) {
-	    pw = getpwnam(user);
-	    if (pw && (pw->pw_uid != uid)) pw = 0;
-	}
-	if (pw == 0) {
-	    user = nh_getenv("USER");
-	    if (user) {
-		pw = getpwnam(user);
-		if (pw && (pw->pw_uid != uid)) pw = 0;
-	    }
-	    if (pw == 0) {
-		pw = getpwuid(uid);
-	    }
-	}
+	struct passwd *pw = get_unix_pw();
 #ifdef SYSCF
 	if (pw && sysopt.wizards[0]) {
-	    if(sysopt.wizards[0] == '*') return TRUE;	/*allow any user to be wizard*/
-	    int pwlen = strlen(pw->pw_name);
-	    char *eop = eos(sysopt.wizards);
-	    char *w = sysopt.wizards;
-	    while( w+pwlen <= eop ){
-		if( ! *w ) break;
-		if( isspace(*w) ){ w++; continue;}
-		if( !strncmp(w, pw->pw_name, pwlen) ){
-		    if( !w[pwlen] || isspace(w[pwlen]) ) return TRUE;
-		}
-		while( *w && !isspace(*w) ) w++;
-	    }
+	    if(check_user_string(sysopt.wizards)) return TRUE;
 	} else
 #endif
 	if (pw && !strcmp(pw->pw_name, WIZARD_NAME)) return TRUE;
@@ -607,4 +578,50 @@ char *name;
 	return;
 }
 
+boolean
+check_user_string(optstr)
+char *optstr;
+{
+	struct passwd *pw = get_unix_pw();
+	if(optstr[0] == '*') return TRUE;	/* allow any user */
+	if(!pw) return FALSE;
+	int pwlen = strlen(pw->pw_name);
+	char *eop = eos(optstr);
+	char *w = optstr;
+	while( w+pwlen <= eop ){
+		if( ! *w ) break;
+		if( isspace(*w) ){ w++; continue;}
+		if( !strncmp(w, pw->pw_name, pwlen) ){
+			if( !w[pwlen] || isspace(w[pwlen]) ) return TRUE;
+		}
+		while( *w && !isspace(*w) ) w++;
+	}
+	return FALSE;
+}
+
+static struct passwd *
+get_unix_pw(){
+	char *user;
+	int uid;
+	static struct passwd *pw = (struct passwd *)0;
+	if(pw) return pw;	/* cache answer */
+
+	uid = getuid();
+	user = getlogin();
+	if (user) {
+	    pw = getpwnam(user);
+	    if (pw && (pw->pw_uid != uid)) pw = 0;
+	}
+	if (pw == 0) {
+	    user = nh_getenv("USER");
+	    if (user) {
+		pw = getpwnam(user);
+		if (pw && (pw->pw_uid != uid)) pw = 0;
+	    }
+	    if (pw == 0) {
+		pw = getpwuid(uid);
+	    }
+	}
+	return pw;
+}
 /*unixmain.c*/
diff --git a/sys/unix/unixunix.c b/sys/unix/unixunix.c
index e333e4ae1..d47ebe7c7 100644
--- a/sys/unix/unixunix.c
+++ b/sys/unix/unixunix.c
@@ -244,6 +244,15 @@ int
 dosh()
 {
 	register char *str;
+# ifdef SYSCF
+	if(   !sysopt.shellers
+	   || !sysopt.shellers[0]
+	   || !check_user_string(sysopt.shellers)
+	){
+		Norep("Unknown command '!'.");
+		return 0;
+	}
+# endif
 	if(child(0)) {
 		if((str = getenv("SHELL")) != (char*)0)
 			(void) execl(str, str, (char *)0);