diff --git a/doc/fixes35.0 b/doc/fixes35.0
index 1396e8c21..3afad9964 100644
--- a/doc/fixes35.0
+++ b/doc/fixes35.0
@@ -182,6 +182,7 @@ allow corpses on floor to be offered at high altars
 allow hero to attempt to offer the Amulet at ordinary altars
 shooting range for crossbow isn't affected by strength; multi-shot volley is
 right-handed boomerang throw travels counterclockwise
+monsters can use ranged attacks over/around boulders, same as hero
 
 
 Platform- and/or Interface-Specific Fixes
diff --git a/include/extern.h b/include/extern.h
index 60aa32df4..e5370436a 100644
--- a/include/extern.h
+++ b/include/extern.h
@@ -1421,7 +1421,7 @@ E int FDECL(ohitmon, (struct monst *,struct obj *,int,BOOLEAN_P));
 E void FDECL(thrwmu, (struct monst *));
 E int FDECL(spitmu, (struct monst *,struct attack *));
 E int FDECL(breamu, (struct monst *,struct attack *));
-E boolean FDECL(linedup, (XCHAR_P,XCHAR_P,XCHAR_P,XCHAR_P));
+E boolean FDECL(linedup, (XCHAR_P,XCHAR_P,XCHAR_P,XCHAR_P,int));
 E boolean FDECL(lined_up, (struct monst *));
 E struct obj *FDECL(m_carrying, (struct monst *,int));
 E void FDECL(m_useupall, (struct monst *,struct obj *));
diff --git a/src/mthrowu.c b/src/mthrowu.c
index 48b7af415..f258c9981 100644
--- a/src/mthrowu.c
+++ b/src/mthrowu.c
@@ -708,9 +708,12 @@ breamu(mtmp, mattk)			/* monster breathes at you (ranged) */
 }
 
 boolean
-linedup(ax, ay, bx, by)
+linedup(ax, ay, bx, by, boulderhandling)
 register xchar ax, ay, bx, by;
+int boulderhandling;	/* 0=block, 1=ignore, 2=conditionally block */
 {
+	int dx, dy, boulderspots;
+
 	tbx = ax - bx;	/* These two values are set for use */
 	tby = ay - by;	/* after successful return.	    */
 
@@ -720,8 +723,22 @@ register xchar ax, ay, bx, by;
 
 	if((!tbx || !tby || abs(tbx) == abs(tby)) /* straight line or diagonal */
 	   && distmin(tbx, tby, 0, 0) < BOLT_LIM) {
-	    if(ax == u.ux && ay == u.uy) return((boolean)(couldsee(bx,by)));
-	    else if(clear_path(ax,ay,bx,by)) return TRUE;
+	    if ((ax == u.ux && ay == u.uy) ? (boolean)couldsee(bx, by) :
+		clear_path(ax, ay, bx, by)) return TRUE;
+	    /* don't have line of sight, but might still be lined up
+	       if that lack of sight is due solely to boulders */
+	    if (boulderhandling == 0) return FALSE;
+	    dx = sgn(ax - bx), dy = sgn(ay - by);
+	    boulderspots = 0;
+	    do {
+		/* <bx,by> is guaranteed to eventually converge with <ax,ay> */
+		bx += dx, by += dy;
+		if (IS_ROCK(levl[bx][by].typ) || closed_door(bx, by))
+		    return FALSE;
+		if (sobj_at(BOULDER, bx, by)) ++boulderspots;
+	    } while (bx != ax && by != ay);
+	    /* reached target position without encountering obstacle */
+	    if (boulderhandling == 1 || rn2(2 + boulderspots) < 2) return TRUE;
 	}
 	return FALSE;
 }
@@ -730,7 +747,11 @@ boolean
 lined_up(mtmp)		/* is mtmp in position to use ranged attack? */
 	register struct monst *mtmp;
 {
-	return(linedup(mtmp->mux,mtmp->muy,mtmp->mx,mtmp->my));
+	boolean ignore_boulders = (throws_rocks(mtmp->data) ||
+				   m_carrying(mtmp, WAN_STRIKING));
+
+	return linedup(mtmp->mux, mtmp->muy, mtmp->mx, mtmp->my,
+		       ignore_boulders ? 1 : 2);
 }
 
 /* Check if a monster is carrying a particular item.
diff --git a/src/priest.c b/src/priest.c
index f791b01e0..1e60d104d 100644
--- a/src/priest.c
+++ b/src/priest.c
@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)priest.c	3.5	2006/05/26	*/
+/*	SCCS Id: @(#)priest.c	3.5	2006/12/27	*/
 /* Copyright (c) Izchak Miller, Steve Linhart, 1989.		  */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -710,9 +710,8 @@ struct monst *priest;
 	ay = y = EPRI(priest)->shrpos.y;
 	troom = &rooms[roomno - ROOMOFFSET];
 
-	if((u.ux == x && u.uy == y) || !linedup(u.ux, u.uy, x, y)) {
+	if ((u.ux == x && u.uy == y) || !linedup(u.ux, u.uy, x, y, 1)) {
 	    if(IS_DOOR(levl[u.ux][u.uy].typ)) {
-
 		if(u.ux == troom->lx - 1) {
 		    x = troom->hx;
 		    y = u.uy;
@@ -734,7 +733,7 @@ struct monst *priest;
 		default: x = troom->hx; y = u.uy; break;
 		}
 	    }
-	    if(!linedup(u.ux, u.uy, x, y)) return;
+	    if (!linedup(u.ux, u.uy, x, y, 1)) return;
 	}
 
 	switch(rn2(3)) {