diff --git a/include/X11/Xlibint.h b/include/X11/Xlibint.h
index cbf3aac3..b4275ebd 100644
--- a/include/X11/Xlibint.h
+++ b/include/X11/Xlibint.h
@@ -207,6 +207,7 @@ struct _XDisplay
 
 	XIOErrorExitHandler exit_handler;
 	void *exit_handler_data;
+        Bool in_ifevent;
 };
 
 #define XAllocIDs(dpy,ids,n) (*(dpy)->idlist_alloc)(dpy,ids,n)
diff --git a/src/ChkIfEv.c b/src/ChkIfEv.c
index 876a850e..327b5eaf 100644
--- a/src/ChkIfEv.c
+++ b/src/ChkIfEv.c
@@ -50,6 +50,7 @@ Bool XCheckIfEvent (
 	int n;			/* time through count */
 
         LockDisplay(dpy);
+        dpy->in_ifevent = True;
 	prev = NULL;
 	for (n = 3; --n >= 0;) {
 	    for (qelt = prev ? prev->next : dpy->head;
@@ -60,6 +61,7 @@ Bool XCheckIfEvent (
 		    *event = qelt->event;
 		    _XDeq(dpy, prev, qelt);
 		    _XStoreEventCookie(dpy, event);
+                    dpy->in_ifevent = False;
 		    UnlockDisplay(dpy);
 		    return True;
 		}
@@ -78,6 +80,7 @@ Bool XCheckIfEvent (
 		/* another thread has snatched this event */
 		prev = NULL;
 	}
+        dpy->in_ifevent = False;
 	UnlockDisplay(dpy);
 	return False;
 }
diff --git a/src/IfEvent.c b/src/IfEvent.c
index ead93dca..a0aed7e3 100644
--- a/src/IfEvent.c
+++ b/src/IfEvent.c
@@ -49,6 +49,7 @@ XIfEvent (
 	unsigned long qe_serial = 0;
 
         LockDisplay(dpy);
+        dpy->in_ifevent = True;
 	prev = NULL;
 	while (1) {
 	    for (qelt = prev ? prev->next : dpy->head;
@@ -59,6 +60,7 @@ XIfEvent (
 		    *event = qelt->event;
 		    _XDeq(dpy, prev, qelt);
 		    _XStoreEventCookie(dpy, event);
+                    dpy->in_ifevent = False;
 		    UnlockDisplay(dpy);
 		    return 0;
 		}
diff --git a/src/OpenDis.c b/src/OpenDis.c
index 5017b040..e1bc2a30 100644
--- a/src/OpenDis.c
+++ b/src/OpenDis.c
@@ -189,6 +189,7 @@ XOpenDisplay (
 	dpy->xcmisc_opcode	= 0;
 	dpy->xkb_info		= NULL;
 	dpy->exit_handler_data	= NULL;
+        dpy->in_ifevent         = False;
 
 /*
  * Setup other information in this display structure.
diff --git a/src/PeekIfEv.c b/src/PeekIfEv.c
index 207cd119..c4e8af0d 100644
--- a/src/PeekIfEv.c
+++ b/src/PeekIfEv.c
@@ -50,6 +50,7 @@ XPeekIfEvent (
 	unsigned long qe_serial = 0;
 
 	LockDisplay(dpy);
+        dpy->in_ifevent = True;
 	prev = NULL;
 	while (1) {
 	    for (qelt = prev ? prev->next : dpy->head;
@@ -63,6 +64,7 @@ XPeekIfEvent (
 			_XStoreEventCookie(dpy, &copy);
 			*event = copy;
 		    }
+                    dpy->in_ifevent = False;
 		    UnlockDisplay(dpy);
 		    return 0;
 		}
diff --git a/src/locking.c b/src/locking.c
index ea5000e1..36530691 100644
--- a/src/locking.c
+++ b/src/locking.c
@@ -452,6 +452,32 @@ static void _XDisplayLockWait(
     }
 }
 
+static void _XLockDisplay(
+    Display *dpy
+    XTHREADS_FILE_LINE_ARGS
+    );
+
+static void _XIfEventLockDisplay(
+    Display *dpy
+    XTHREADS_FILE_LINE_ARGS
+    )
+{
+    /* assert(dpy->in_ifevent); */
+}
+
+static void _XIfEventUnlockDisplay(
+    Display *dpy
+    XTHREADS_FILE_LINE_ARGS
+    )
+{
+    if (dpy->in_ifevent)
+        return;
+
+    dpy->lock_fns->lock_display = _XLockDisplay;
+    dpy->lock_fns->unlock_display = _XUnlockDisplay;
+    UnlockDisplay(dpy);
+}
+
 static void _XLockDisplay(
     Display *dpy
     XTHREADS_FILE_LINE_ARGS
@@ -478,6 +504,10 @@ static void _XLockDisplay(
 #endif
     _XIDHandler(dpy);
     _XSeqSyncFunction(dpy);
+    if (dpy->in_ifevent) {
+        dpy->lock_fns->lock_display = _XIfEventLockDisplay;
+        dpy->lock_fns->unlock_display = _XIfEventUnlockDisplay;
+    }
 }
 
 /*