I'd also check into the free spyhunter software, I was reading through some recent logs on other forums that suggested trend micro, avg and others missed the zlob variant, whereas spyhunter finds it BUT your Hijackthis log shows "FILE MISSING" after the suspect wxdbpfvo.dll listed as [Parasite causing false spyware warnings and connecting to fake "security sites" - member of the FakeAlert aka SmitFraud malware family]

The file missing part means your apps found the infected file and removed them, or your suspect file is hiding itself until later...