Last Vulnerability Protection Update causing severe problems, Safari hangs, Mail cannot connect etc

Since the last Vulnerability Update (I guess 2-3 weeks ago), i am having severe problems with may 3.33 Ghz iMac under OSX 10.6.4, 4GB Ram installed.

 

Safari hangs after a couple of minutes, when I'm selecting URL's within a Web-page, or Mail can not connect to the Internet, only after a few Restarts it is sometimes working.

 

Thoday all of those problems disappeared, after I have disabled Vulnerability Protection, now everything is working like it did before that Update, Auto-Protect is still enabled.

 

NAV: Latest, Vulnerability Protection Engine for Mac: 3.1.0, Vulnerability Protection: Latest, Live Update 5.1.2, NAV for mav Vers. 11.1.1

 

The Problems are reproducable also on the latest MacMini, please let me know, if you need more info