@mchiasson: glad that you've solved this issue. Just a question. What were the definitions on your network before this? The SEP/SAV were protected by W32.Qakbot since May 7th and was protected since May 12 which is your last definitions before the update.
Here's the release dates from Symantec for W32.Qakbot :
Initial Rapid Release version May 7, 2009 revision 001
Latest Rapid Release version May 13, 2009 revision 037
Initial Daily Certified version May 7, 2009 revision 003
Latest Daily Certified version May 12, 2009 revision 039
Initial Weekly Certified release date May 13, 2009