Ports blocked from recent update

Since the last update Avast is blocking lot new Ports like the port used for MSN live messenger.
Confirmed by turning off On access protection control was able to login in straight away.
Confirmed it also has same effect on XP and my Vista computers.
Is there some work around for this, is it new feature that im yet to discover how to turn it off
other than disabling Avast?

avast does not block ports. Is scans http traffic.
Which firewall do you use?

No third party firewall installed, only Windows firewall running

Comfirmed after turning off windows firewall, both XP and Vista now startup normally and login to messenger.
My question now is why do i now have to turn off windows firewall, problem arrived with Avast update.
Been running windows firewall and avast is same config for 2 weeks with no problems?

Now i understand the problem a bit better, i"ll reword it.
It seems since the last update, interaction between Windows Firewall and Avast together are causing my port issues.
If i turn either of them off issue goes away.
After turning Windows firewall off, I then rebooted machines.
I turn Windows Firewall back on, I rebooted machines all port issues are back to normal very WEIRD.
Thanks for you help…

I think Windows Firewall at Vista is more configurable than on XP (outbound protection), but anyway… it shouldn’t happen this way. It’s strange.
Glad that you, at last, get it solved.