Event Viewer ESENT error messages

Ever since Avast 5 has been installed, I’m getting a whole lot of ESENT error messages in Event Viewer (XP Home SP3).


http://img197.imageshack.us/img197/6319/errormsgb.th.jpg

Clicking on any one of them says:

"Event Type: Error
Event Source: ESENT
Event Category: General
Event ID: 490
Date: 1/29/2010
Time: 00:16:58
User: N/A
Computer: FUZZY
Description:
svchost (1148) An attempt to open the file “C:\WINDOWS\system32\CatRoot2{F750E6C3-38EE-11D1-85E5-00C04FC295EE}\catdb” for read / write access failed with system error 32 (0x00000020): "The process cannot access the file because it is being used by another process. ". The open file operation will fail with error -1032 (0xfffffbf8).

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp." Each one of the errors has a different code. What gives?

I too have the exact same error on two pc. (Avast 5.0.418)
I hope someone can solve it.