diff --git a/modules/im/ximcp/imLcFlt.c b/modules/im/ximcp/imLcFlt.c
index cef4dbf..748c501 100644
--- a/modules/im/ximcp/imLcFlt.c
+++ b/modules/im/ximcp/imLcFlt.c
@@ -46,15 +46,13 @@ _XimLocalFilter(Display *d, Window w, XEvent *ev, XPointer client_data)
     static char	 buf[256];
     DefTree	*b = ic->private.local.base.tree;
     DTIndex	 t;
+    unsigned int state, tmpstate;
 
     if(ev->xkey.keycode == 0)
 	return (False);
 
     XLookupString((XKeyEvent *)ev, buf, sizeof(buf), &keysym, NULL);
 
-    if(IsModifierKey(keysym))
-	return (False);
-
     if(keysym >= XK_braille_dot_1 && keysym <= XK_braille_dot_8) {
 	if(ev->type == KeyPress) {
 	    ic->private.local.brl_pressed |=
@@ -80,12 +78,41 @@ _XimLocalFilter(Display *d, Window w, XEvent *ev, XPointer client_data)
 	return(True);
     }
 
-    if(   (ev->type != KeyPress)
-       || (((Xim)ic->core.im)->private.local.top == 0 ) )
+    if(((Xim)ic->core.im)->private.local.top == 0 )
 	return(False);
 
+    if(ev->type == KeyPress) {
+	state = ev->xkey.state;
+
+	/* Abuse thai data to remember information about last pressed key */
+	ic->private.local.thai.keysym = keysym;
+	ic->private.local.thai.comp_state = (int)state;
+
+	/* Never filter modifier presses */
+	if(IsModifierKey(keysym))
+	    return(False);
+    } else {
+	/* For lookup, we use the state at the time when the key was */
+	/* pressed, because this state was no affected by the modifier */
+	/* that is mapped to the key. */
+	state = (unsigned int)ic->private.local.thai.comp_state;
+
+	/* Lookup with the original state */
+	tmpstate = ev->xkey.state;
+	ev->xkey.state = state;
+	XLookupString((XKeyEvent *)ev, buf, sizeof(buf), &keysym, NULL);
+	ev->xkey.state = tmpstate;
+
+	/* Key releases are only considered for modifiers, and only if */
+	/* no other key has been pressed in between */
+	if(!IsModifierKey(keysym) ||
+	   ic->private.local.thai.keysym != keysym)
+	    return(False);
+
+    }
+
     for(t = ic->private.local.context; t; t = b[t].next) {
-	if(((ev->xkey.state & b[t].modifier_mask) == b[t].modifier) &&
+	if(((state & b[t].modifier_mask) == b[t].modifier) &&
 	   (keysym == b[t].keysym))
 	    break;
     }
@@ -93,24 +120,28 @@ _XimLocalFilter(Display *d, Window w, XEvent *ev, XPointer client_data)
     if(t) { /* Matched */
 	if(b[t].succession) { /* Intermediate */
 	    ic->private.local.context = b[t].succession;
-	    return(True);
+	    return(ev->type == KeyPress);
 	} else { /* Terminate (reached to leaf) */
 	    ic->private.local.composed = t;
 	    ic->private.local.brl_committed = 0;
 	    /* return back to client KeyPressEvent keycode == 0 */
 	    ev->xkey.keycode = 0;
+	    ev->xkey.type = KeyPress;  /* needed for KeyRelease */
+	    ev->xkey.state = state;    /* needed for KeyRelease */
 	    XPutBackEvent(d, ev);
 	    /* initialize internal state for next key sequence */
 	    ic->private.local.context = ((Xim)ic->core.im)->private.local.top;
 	    return(True);
 	}
     } else { /* Unmatched */
-	if(ic->private.local.context == ((Xim)ic->core.im)->private.local.top) {
+	/* An unmatched key release does not abort a compose sequence. */
+	if(ic->private.local.context == ((Xim)ic->core.im)->private.local.top ||
+	   ev->type == KeyRelease) {
 	    return(False);
 	}
 	/* Error (Sequence Unmatch occured) */
 	/* initialize internal state for next key sequence */
 	ic->private.local.context = ((Xim)ic->core.im)->private.local.top;
-	return(True);
+	return(ev->type == KeyPress);
     }
 }
diff --git a/modules/im/ximcp/imLcIc.c b/modules/im/ximcp/imLcIc.c
index 53d53ef..c072808 100644
--- a/modules/im/ximcp/imLcIc.c
+++ b/modules/im/ximcp/imLcIc.c
@@ -180,7 +180,7 @@ _XimLocalCreateIC(
 			values, XIM_CREATEIC, True)) {
 	goto Set_Error;
     }
-    ic_values.filter_events = KeyPressMask;
+    ic_values.filter_events = KeyPressMask | KeyReleaseMask;
     _XimSetCurrentICValues(ic, &ic_values);
     if(_XimSetICDefaults(ic, (XPointer)&ic_values,
 				XIM_SETICDEFAULTS, res, num) == False) {