Ok, good try, but, please, a bit more detail?
What version of ULib?
(Are you running the latest "release" of ULib downloaded from ulyssesmod.net(2.3)? Or did you get our 'beta' SVN from ulyssesmod.net)
When do you get that error? (Run a command on client? Run a command on server? What command?)
(At server startup? At client join?)
Which console? Server or Client game?