Hi,
You have entered the account info as a Jabber Name and not chosen the Google option
With iChat Open go to the iChat Menu > Preferences > Accounts
Click on the Plus Button at the bottom of the List.
In the top item in the new pane Choose GoogleTalk.
Add your ID exactly as it appears when you Log in to the Web Mail page at Google (Mail seems to except either ending, @google.com or @gmail.com but the Google Talk server does not)
Enter in the password
Click the Done button
You should now have Buddy List that Logs On
In the Account list in iChat you will now have at least three Accounts Listed (the faulty one, the new one and Bonjour)
If you then check the Server Setting tab/button on both the "google" accounts you will find the new one says the server in talk.google.com
The other will use the last part of your ID (in your case you entered a name/ID ending @gmail.com).
The reason for your confusion is that those Google Instructions are for iChat 3
You have "Missed" the bit about changing the Server Name in the Server Setting tab to talk.google.com as in fact you can add it as a Jabber account and then change the server name the same way.
You could change the server info in the "old" account or you can highlight it the list then press the minus button to Delete it.
One other thing.
It is important that Talk is Enabled in your everyday Google Account Setting (Not the mail ones).
This does add the Chat option to the Mail Web page and of course allows iChat to use the GoogleTalk servers.
I have several Jabber Accounts including Google as well as several AIM valid Logins.
I don't find the Google servers go Off line or drop connections any more (Nowadays) than the AIM ones or other Jabber servers.
9:21 PM Monday; May 23, 2011
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb( 10.6.7)
Mac OS X (10.6.7),
"Limit the Logs to the Bits above Binary Images." No, Seriously
Message was edited by: Ralph Johns (UK)