OK, I'll kick it off. A beauty in V6 (and possibly V7) was discovered by the kiddies in Elec Eng; by sending a signal with an appropriately-crafted negative value (as determined from inspecting <user.h>) you could overwrite u.u_uid with zero... Needless to say I scrambled to fix that one on my 11/40 network! -- Dave Horsfall DTM (VK2KFU) "Those who don't understand security will suffer."