Check if MailboxEvaluateAllAutomaticRulesSubMin and MailboxEvaluateAllAutomaticRules both are enabled. Only one of them should be enabled. If you have only MailboxEvaluateAllAutomaticRulesSubMin and it is failing to get lock, then you need to tune it to run at longer intervals for more than 10 seconds. In general, this happens due to high volume, DB tuning (Mostly with MS SQL Serer) etc.
_Dhiraj Patil
------------------------------
Dhiraj Patil
------------------------------