Kaspersky Update befowls Exchange with Sybari

This morning at 11:40 our Exchange 2003 server updated the kaspersky antivirus scan engine. That is part of Microsoft (Sybari) Antigen. A few minutes later I began receiving emails about a scantime timeout and when I checked I saw that no mail was being delivered anymore.
After spending an hour on hold with Microsoft waiting for support I changed tactics and called my TAM. He told me I was still 35th or so in the phone queue (down from a couple hundred) and that the problem was a bad Kasperski virus definition update. (that is what I suspected). I disabled Sybari scan jobs (once I could get into its admin gui) and updated Kasperski to a newer definition set. All told two admins wasted three hours on this today and our company couldn’t send or receive email for most of that time.
While bad virus def updates have hosed our server in the past (usually its kaspersky), I have never had this kind of hold time. I am really unhappy with the quality of support now that Microsoft owns Antigen.