I think pnMessages is stable enought and has enought features to stop support for the old pmBOX module.
I have deleted all pmBOX downloads from the Downloads section of this site.
I suggest that all pmBOX users migrate their websites to pnMessages:

• Don't delete or inactivate pmBOX you will need it later, if you do it now you will loose all messages !!
  
• upload pmMessages' files, regenerate module's list
  
• install pnMessages and during installation, choose to import pmBOX table
  
• activate pnMessages
  
• test that pnMessages works OK
  
• only after that inactivate and remove pmBOX (of course as usual you began all this procedure doing a backup of your database, just in case, isn't it ?)

L'aquarium de JMV is also running pnMessages starting from today.

pnmessages still has a problem with timesewrap, it doesnt get the user time and stamp the website's time zone instead, that slong with so many other bugs like default sorting and such

ok, thanks

Have you reported the problem in the pnMessages tracker at the NOC ? If not do it please, trying to use an old module like pmBOX is certainly not a good solution (believe me, I know the code well )
if you find some bugs in pnMessages the solution is to fix the bug and make pnMessages better.