HI,
The Yahoo option does not do Video and Audio chats.
The GoogleTalk login depends on what app the Buddy is using.
Jabber apps tend to use a process called Jingle
to connect.
This Link claims Google had a hand in creating it but that they also don't use the current Draft Standard.
iChat and Messages uses SIP (Session Initiation Protocol) to Connect.
For iChat users this means it will not connect to Jabber Apps on Macs or PCs to do Video/Audio Chats
Nor will it connect to the GoogleTalk App for PCs.
The Plugin for Web Browsers (PC or Mac versions) are also excluded and Google include the Jingle Protocol (or their Version) in this as well.
Of course these Google variants also have difficulty with other Jabber Apps (that can do Jingle Video) as well.
Just to be clear.
It is iChat to iChat only in Jabber.
9:14 PM Tuesday; October 2, 2012
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"
iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.2)
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
Couple of iPhones and an iPad
"Limit the Logs to the Bits above Binary Images." No, Seriously