Hi, It should be noted that ProtoVer Sample IMAP testsuite has been released with 3 unpublished bugs. Now it looks like that Kerio MailServer preauth bug has been fixed. Kerio MailServer 6.1.3 changelog: """ Version 6.1.3 Patch 1 - March 9, 2006 - Fixed possible crash when handling special crafted IMAP LOGIN command. """ The bug itself is really simple: $ ls PROTOVER_SAMPLE_IMAP-1.0/audit/ iaemailserver-5.3.4 keriomailserver-6.1.2 merak-8.3.0 $ cat PROTOVER_SAMPLE_IMAP-1.0/audit/keriomailserver-6.1.2 a001 LOGIN {4294967294} LITERAL TOKEN a002 LOGOUT Regards, Evgeny Legerov www.gleg.net