> the accordant annoyance with this arrangement is that neither a 
> thunderbird copy operation, nor an X selection on a thunderbird window, 
> are available within VNC for pasting.
even if this problem gets a solution, i doubt it will include the 
capability to click a link in thunderbird and thereby bring up a page in 
the firefox running within vnc.

for that, the best i can imagine might be an extension that implements a 
toolbar button that does both paste and goto-url operations all in one 
click.  anyone heard of such a button?