[Sat May 24 02:02:51.025715 2014] [:error] [pid 14334] [client ***] ModSecurity: Access denied with code 400 (phase 1). Operator GT matched 512 at ARGS_GET:_uids
such params should be POSt and not GET
affects mailboxes with a lot of messages and seems to be a very new problem with RC 1.0.x