Mouse Cut/Paste with emacs

[John M Phillips]

The cut/paste function in emacs appears to be injured if not broken. 
External selection from other programs do not work consistently. Here, cut 
is done with click-and-drag with mouse-button-1 and paste is done with
mouse-button-2.

The first "cut" from another X11 program does paste correctly into emacs. 
But once the is a selection internal to emacs, external selections no 
longer work with the emacs paste function.  If I double-click with 
mouse-button-3, then emacs will again respond to external selections.

Any suggestions?
John M Phillips