Two problems surfaced when I upgraded my Mac to Mavericks (OS X 10.9).
First, the old Java SE installation was removed (actually, some linkages were destroyed), so a Maple launch puts up a dialog "need to install Java." Apple hasn't yet (10/23/13) updated the software database links --- installation fails with a "can't find software" error. I reinstalled Java using the version at http://support.apple.com/downloads/DL1572/en_US/JavaForOSX2013-05.dmg. (The links can be redone, it's just easier to reinstall.)
Second, the (new?) structure for /Library/Frameworks made my Maple license invalid. I dug out the old email with my activation code, then re-activated.
And all is now copacetic.