It depends on what you want to do with the message. Win32::GUI is probably the right tool (it might have exactly what you need already), but since that's a bit vague...

I suspect that if you state what you want on a higher level of abstraction, Win32::GUI will be useful in some way, at least as the proper base to build on.

Get both the PPM and the source distribution with the docs and stuff.

http://sourceforge.net/projects/perl-win32-gui

If you decide to go with Win32::GUI, this mailing list is highly recommended:

http://lists.sourceforge.net/lists/listinfo/perl-win32-gui-users

/J