Hi,
On the Reinstall, did you run the COMBO installer afterwards ?
In this case Skype proves nothing.
Each Download of Skype comes with it's own Port listed in the Preferences. It varies from Download to Download.
The way the Mac firewall works is the App is Certificated in Leopard and Snow Leopard and you do not have to open specific ports.
If you are using UPnP in the routing device Skype will work.
If you are not and are using port Forwarding but have not Port Forwarded the port listed Skype will use a Fall back port (Normally port 80 - web Browsing or 110 - Mail) to get around this and Skype will work.
At this Point go to the Application Folder and do "Get Info" on iChat (Apple Key and I together).
In the panel that pops up in Plugins is everything marked as On ?
If this is true the go to the View Menu > Messages and chose another Style other than Balloons (you will have to open a Text Chat window even if you send nothing)
8:24 PM Wednesday; January 27, 2010
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"