hmm. interesting… the reason I was thinking of Avast 4.5 is the introduction of the new network/internet service…

Since I could not see the problem before this new version, and since the symptom I have is when I get Avast icon first other application cannot start, I was thinking of some sort of interaction with the firewall tool or something of this kind…
may be I was jumping to conclusion…

Ok… will do some more home work, play around with startup delayer and see which guy should be started last to avoid the hang to happen…