A link that stands out is http://www.devdaily.com/blog/post/jfc-swing/handling-main-mac-menu-in-swing-application/ however the menu bar under Mac OS X displays as the packag
As I understand you want to rename your application menu shown on the os x menu bar. Well, I didn't find a system property but I found a command line option:
-Xdock:name="YourNameHere"
that worked for me.
BTW: The syystem property com.apple.mrj.application.apple.menu.about.name is for renaming the about menu item in your application menu, not the menu bar itself
See this link here (the old link was probably killed sometime after the sun-oracle-aquisition).