Its a nice trick, I knew it and this is working on retail/l2off/l2java... Tho its not a bug, nor exploit, just a glitch which has not been realized by the NCSOFT.
That is why we all do clan hall bsoe after PK, change subclass to a lowlevel subclass sub (eg.: dwarfie), and get a guard from the town, run back to clan hall, and close doors. If you got killed nobody will steal your items (I think none of your clanmates want to rob you) and after death you can choose "TO CLAN HALL" so if you still have karma you can do it since the guard is still in your CH (closed doors).