That's a system update. I don't think there's really anything you can do about it directly.
Depending on what else the server is used for, you might relieve cache-pressure by using the optimize for ad hoc setting: http://msdn.microsoft.com/en-us/library/cc645587.aspx
- Gus "GSquared", RSVP, OODA, MAP, NMVP, FAQ, SAT, SQL, DNA, RNA, UOI, IOU, AM, PM, AD, BC, BCE, USA, UN, CF, ROFL, LOL, ETC
Property of The Thread
"Nobody knows the age of the human race, but everyone agrees it's old enough to know better." - Anon