Gdk-WARNING **: Connection to display localhost:10.0 appears to be untrusted

Have you ever had problems running X applications over ssh that did not involve issues with xauth. Here is a tip I found after getting error like this:

Connection to display localhost:10.0 appears to be untrusted. Pointer and keyboard grabs and inter-client communication may not work as expected.

or

Warning: untrusted X11 forwarding setup failed: xauth key data not generated

So, instead of simply using "ssh -X user@host", try using "ssh -2 -C -Y user@host" instead.

-2 Forces ssh to try protocol version 2 only.
-C Requests compression of all data ... which can be desirable in low bandwidth situations.
-Y Enables trusted X11 forwarding.

Using -Y is what got rid of the warning and subsequent functionality issue with the X application. But the compression helped speed things up quite a bit also.

Even with these new command line parameters I still get the warning:

Warning: No xauth data; using fake authentication data for X11 forwarding.

Anyone know what the issue there is?

Anyway, I hope that helps you as much as it did me.