pc-selection-mode, `C-x C-x' and transient-mark-mode?

[Steven T. Hatton]

I've discovered that having 
(custom-set-variables 
;;...
'(pc-selection-mode t nil (pc-select))
;;...
)
causes `C-x C-x' to behave differently than it does when pc-selection-mode is 
nil.  Here are my observations:

With pc-selection-mode:

I select a region and then `C-x C-x'.  The highlighting disappears, and the 
cursor is moved to the location of point.  The region is still selected, as 
is evidenced by the fact I can 'C-w' to kill it.

With `$ emacs -q&' then M-x transient-mark-mode <RET>':

The behavior is basically the same except that the highlighting does not 
disappear when point and mark are swapped using `C-x C-x'.

Is this intended behavior?

GNU Emacs 21.3.50.1 (latest CVS as of yesterday)
SuSE Linux 9.1 (i586) (latest patches)
-- 
Regards,
Steven