diff --git a/doc/fixes34.1 b/doc/fixes34.1
index 8c8576903..7fe5b8c27 100644
--- a/doc/fixes34.1
+++ b/doc/fixes34.1
@@ -206,6 +206,7 @@ engulfing green slime as a purple worm was causing stoning not sliming
 zero entries in DUNGEON, MONSTERS, et al, of config file are now treated
 	as preserving the default rather than being ignored
 enlightenment: don't misreport polymorphed lycanthrope as "in beast form"
+remove TIMED_DELAY from the features checked for version compatibility
 
 
 Platform- and/or Interface-Specific Fixes
diff --git a/src/version.c b/src/version.c
index 02f577ec7..669d22d9c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)version.c	3.4	1999/12/01	*/
+/*	SCCS Id: @(#)version.c	3.4	2002/08/14	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -64,7 +64,13 @@ boolean complain;
 	    if (complain)
 		pline("Version mismatch for file \"%s\".", filename);
 	    return FALSE;
-	} else if (version_data->feature_set != VERSION_FEATURES ||
+	} else if (
+#ifndef IGNORED_FEATURES
+		   version_data->feature_set != VERSION_FEATURES ||
+#else
+		   (version_data->feature_set & ~IGNORED_FEATURES) !=
+			  (VERSION_FEATURES & ~IGNORED_FEATURES) ||
+#endif
 		   version_data->entity_count != VERSION_SANITY1 ||
 		   version_data->struct_sizes != VERSION_SANITY2) {
 	    if (complain)
diff --git a/util/makedefs.c b/util/makedefs.c
index 46c21c2f8..0c27da698 100644
--- a/util/makedefs.c
+++ b/util/makedefs.c
@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)makedefs.c	3.4	2002/03/03	*/
+/*	SCCS Id: @(#)makedefs.c	3.4	2002/08/14	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* Copyright (c) M. Stephenson, 1990, 1991.			  */
 /* Copyright (c) Dean Luick, 1990.				  */
@@ -406,6 +406,18 @@ do_rumors()
 	return;
 }
 
+/*
+ * 3.4.1: way back in 3.2.1 `flags.nap' became unconditional but
+ * TIMED_DELAY was erroneously left in VERSION_FEATURES and has
+ * been there up through 3.4.0.  Simply removing it now would
+ * break save file compatibility with 3.4.0 files, so we will
+ * explicitly mask it out during version checks.
+ * This should go away in the next version update.
+ */
+#define IGNORED_FEATURES	( 0L \
+				| (1L << 23)	/* TIMED_DELAY */ \
+				)
+
 static void
 make_version()
 {
@@ -465,9 +477,6 @@ make_version()
 #endif
 #ifdef SCORE_ON_BOTL
 			| (1L << 21)
-#endif
-#ifdef TIMED_DELAY
-			| (1L << 23)
 #endif
 		/* data format [COMPRESS excluded] (27..31) */
 #ifdef ZEROCOMP
@@ -569,6 +578,10 @@ do_date()
 		version.incarnation, ul_sfx);
 	Fprintf(ofp,"#define VERSION_FEATURES 0x%08lx%s\n",
 		version.feature_set, ul_sfx);
+#ifdef IGNORED_FEATURES
+	Fprintf(ofp,"#define IGNORED_FEATURES 0x%08lx%s\n",
+		(unsigned long) IGNORED_FEATURES, ul_sfx);
+#endif
 	Fprintf(ofp,"#define VERSION_SANITY1 0x%08lx%s\n",
 		version.entity_count, ul_sfx);
 	Fprintf(ofp,"#define VERSION_SANITY2 0x%08lx%s\n",