Version:            (using KDE KDE 3.2.3)
Installed from:    Compiled From Sources

If you have MacOS-style menu bars enabled on a Xinerama display, the menu should appear at the top of the screen that the application is currently in, instead of the screen where the application was launched.  At higher resolutions, having the menu on the wrong screen means your mouse almost has to take a pilgrimage to get back and forth between the menu and the application.

Also, for some windows the menu bar doesn't even appear on the screen the window was opened in.  For example, new email messages from KMail always have their menu on Screen 1, even if they were opened in Screen 2.

As a final nitpicking detail, it would be really nice if the items in the desktop menu were a bit more widely spaced than normal menus.  Since it's going across the whole screen, it has plenty of room, and making the entries wider would counter the Fitt's law time penalty for having the menus farther from the application.