Please add support on Special:Userrights to an user resign on any level without the need to keep the default setting ($wgGroupPermissions['bureaucrat']['userrights'] = true;) and without the need to that user having bureaucrat bits. E.g., a sysop can be able to remove their sysop bits, a oversight can be able to remove their oversight bits etc.
In the meantime, please delete the file http://svn.wikimedia.org/viewvc/mediawiki/trunk/extensions/Resign/OBSOLETE?view=log :)
Best regards
Version: unspecified
Severity: enhancement