Your package MegaMek failed to build from source in current rawhide. http://koji.fedoraproject.org/koji/taskinfo?taskID=6930596 For details on mass rebuild see https://fedoraproject.org/wiki/Fedora_21_Mass_Rebuild
Created attachment 903345 [details] build.log
Created attachment 903346 [details] root.log
Created attachment 903347 [details] state.log
This package hasn't been updated in Fedora since 2008. It should really be retired. I have done so in the master branch.