Jerry, the clipboard has suddenly stopped working under Windows.  The following change:
 
2002-04-23  Jerry James  <james@xemacs.org>
 
 * select.c (Fown_selection_internal): Document connection with
        interprogram-cut-function.
 * select.c (Fget_selection_internal): return Qnil if XEmacs owns
        the selection and it does not need coercion.
        Document connection with interprogram-paste-function.
 
 
has done it. (Verified -- I backed out your change, and the problem went away.)  The symptoms are this:
 
i have f3 bound to copy-primary-selection, and f4 bound to yank-clipboard-selection.
 
if i select text, hit f3, then move a bit, and hit f4, it used to work, but now i get the error
 
"there is no clipboard selection".
 
can you please take a look and see what's broken?  if you can't get to it right away i suggest backing out the change and putting it back again when it's working.
 
ben