diff --git a/Xext/xtest.c b/Xext/xtest.c
index bf27eb590..2985a4ce6 100644
--- a/Xext/xtest.c
+++ b/Xext/xtest.c
@@ -502,10 +502,11 @@ XTestSwapFakeInput(ClientPtr client, xReq * req)
 
     nev = ((req->length << 2) - sizeof(xReq)) / sizeof(xEvent);
     for (ev = (xEvent *) &req[1]; --nev >= 0; ev++) {
+        int evtype = ev->u.u.type & 0x177;
         /* Swap event */
-        proc = EventSwapVector[ev->u.u.type & 0177];
+        proc = EventSwapVector[evtype];
         /* no swapping proc; invalid event type? */
-        if (!proc || proc == NotImplemented) {
+        if (!proc || proc == NotImplemented || evtype == GenericEvent) {
             client->errorValue = ev->u.u.type;
             return BadValue;
         }