* jabber-keepalive.el (jabber-whitespace-ping-do): Ignore errors.

Sometimes this fails because the connection is closed.  Not sure
exactly why this happens, but the sentinel function should discover
the lost connection anyway, and having an error signalled in a timer
function doesn't help anyone.

jabber-keepalive.el

@@ -169,7 +169,7 @@ accounts."
 
 (defun jabber-whitespace-ping-do ()
   (dolist (c jabber-connections)
-    (jabber-send-string c " ")))
+    (ignore-errors (jabber-send-string c " "))))
 
 (provide 'jabber-keepalive)