diff -Naur xbiff.orig/Mailbox.c xbiff/Mailbox.c
--- xbiff.orig/Mailbox.c	Fri Feb  2 21:50:28 2001
+++ xbiff/Mailbox.c	Fri Feb  2 23:27:44 2001
@@ -136,6 +136,10 @@
 	offset (check_command), XtRString, NULL},
     { XtNvolume, XtCVolume, XtRInt, sizeof(int),
 	offset (volume), XtRString, "33"},
+    { XtNpitch, XtCPitch, XtRInt, sizeof(int),
+	offset (pitch), XtRString, "-1"},
+    { XtNduration, XtCDuration, XtRInt, sizeof(int),
+	offset (duration), XtRString, "-1"},
     { XtNonceOnly, XtCBoolean, XtRBoolean, sizeof(Boolean),
 	offset (once_only), XtRImmediate, (XtPointer)False },
     { XtNfullPixmap, XtCPixmap, XtRBitmap, sizeof(Pixmap),
@@ -674,6 +678,29 @@
 static void beep (w)
     MailboxWidget w;
 {
+    XKeyboardControl kc;
+    XKeyboardState ks;
+    unsigned long vm = 0;
+
+    if (w->mailbox.pitch != -1)
+	vm |= KBBellPitch;
+    if (w->mailbox.duration)
+	vm |= KBBellDuration;
+
+    if (vm) {
+	XGetKeyboardControl (XtDisplay (w), &ks);
+	kc.bell_pitch = w->mailbox.pitch;
+	kc.bell_duration = w->mailbox.duration;
+	XChangeKeyboardControl (XtDisplay (w), vm, &kc);
+    }
+
     XBell (XtDisplay (w), w->mailbox.volume);
+
+    if (vm) {
+	kc.bell_pitch = ks.bell_pitch;
+	kc.bell_duration = ks.bell_duration;
+	XChangeKeyboardControl (XtDisplay (w), vm, &kc);
+    }
+
     return;
 }
diff -Naur xbiff.orig/Mailbox.h xbiff/Mailbox.h
--- xbiff.orig/Mailbox.h	Fri Feb  2 21:50:28 2001
+++ xbiff/Mailbox.h	Fri Feb  2 22:08:08 2001
@@ -48,6 +48,8 @@
 
 /* Int: volume for bell */
 #define XtNvolume "volume"
+#define XtNpitch "pitch"
+#define XtNduration "duration"
 #define XtNfullPixmap "fullPixmap"
 #define XtNfullPixmapMask "fullPixmapMask"
 #define XtNemptyPixmap "emptyPixmap"
@@ -57,6 +59,8 @@
 
 #define XtCCheckCommand "CheckCommand"
 #define XtCVolume "Volume"
+#define XtCPitch "Pitch"
+#define XtCDuration "Duration"
 #define XtCPixmapMask "PixmapMask"
 #define XtCFlip "Flip"
 #define XtCShapeWindow "ShapeWindow"
diff -Naur xbiff.orig/MailboxP.h xbiff/MailboxP.h
--- xbiff.orig/MailboxP.h	Fri Feb  2 21:50:28 2001
+++ xbiff/MailboxP.h	Fri Feb  2 22:05:35 2001
@@ -61,6 +61,8 @@
     String check_command;		/* command to exec for mail check */
     Boolean flipit;			/* do flip of full pixmap */
     int volume;				/* bell volume */
+    int pitch;                          /* bell pitch */
+    int duration;                       /* bell duration */
     Boolean once_only;			/* ring bell only once on new mail */
     /* local state */
     GC gc;				/* normal GC to use */
diff -Naur xbiff.orig/xbiff.c xbiff/xbiff.c
--- xbiff.orig/xbiff.c	Fri Feb  2 21:50:28 2001
+++ xbiff/xbiff.c	Fri Feb  2 21:59:24 2001
@@ -42,10 +42,12 @@
 char *ProgramName;
 
 static XrmOptionDescRec options[] = {
-{ "-update", "*mailbox.update", XrmoptionSepArg, (caddr_t) NULL },
-{ "-file",   "*mailbox.file", XrmoptionSepArg, (caddr_t) NULL },
-{ "-volume", "*mailbox.volume", XrmoptionSepArg, (caddr_t) NULL },
-{ "-shape",  "*mailbox.shapeWindow", XrmoptionNoArg, (caddr_t) "on" },
+{ "-update",   "*mailbox.update", XrmoptionSepArg, (caddr_t) NULL },
+{ "-file",     "*mailbox.file", XrmoptionSepArg, (caddr_t) NULL },
+{ "-volume",   "*mailbox.volume", XrmoptionSepArg, (caddr_t) NULL },
+{ "-pitch",    "*mailbox.pitch", XrmoptionSepArg, (caddr_t) NULL },
+{ "-duration", "*mailbox.duration", XrmoptionSepArg, (caddr_t) NULL },
+{ "-shape",    "*mailbox.shapeWindow", XrmoptionNoArg, (caddr_t) "on" },
 };
 
 static XtActionsRec xbiff_actions[] = {
@@ -62,6 +64,8 @@
 "    -file file                     file to watch",
 "    -update seconds                how often to check for mail",
 "    -volume percentage             how loud to ring the bell",
+"    -pitch hertz                   pitch of the bell",
+"    -duration milliseconds         how long to ring the bell",
 "    -bg color                      background color",
 "    -fg color                      foreground color",
 "    -rv                            reverse video",
diff -Naur xbiff.orig/xbiff.man xbiff/xbiff.man
--- xbiff.orig/xbiff.man	Fri Feb  2 21:50:28 2001
+++ xbiff/xbiff.man	Fri Feb  2 23:19:46 2001
@@ -61,6 +61,14 @@
 .B \-volume \fIpercentage\fP
 This option specifies how loud the bell should be rung when new mail comes in.
 .TP 8
+.B \-pitch \fIhertz\fP
+This option specifies the pitch in hertz at which the bell should be
+rung.
+.TP 8
+.B \-duration \fImilliseconds\fP
+This option specifies how long in milliseconds the bell should be rung
+for.
+.TP 8
 .B \-shape
 This option indicates that the mailbox window should be shaped if masks for
 the empty or full images are given.
@@ -199,7 +207,24 @@
 stat(2)
 .SH BUGS
 The mailbox bitmaps are ugly.
+
+Setting the
+.B -pitch
+or
+.B -duration
+options will causes
+.I xbiff
+to set the X server's global bell pitch or duration for the display
+while the bell is rung.  If any other program rings the bell before
+.I xbiff
+restores the pitch and duration, it will use these values.  If two
+.I xbiffs
+try to ring the bell with different pitches or durations at the same
+time, it is possible that the defaults will not be correctly restored.
+If this happens, you can restore them by running
+.B xset \-b on.
 .SH AUTHOR
 Jim Fulton, MIT X Consortium
-.br
-Additional hacks by Ralph Swick, DEC/MIT Project Athena
+
+Additional hacks by Ralph Swick, DEC/MIT Project Athena and David
+Richerby <davidr@chiark.greenend.org.uk>