If your phone is on Android 2.2, you can check out if you have this issue at your end. Several Android handset owners seem to be facing an issue with their handsets whereby they do not seem to be receiving notifications for new messages sent to them by their friends on GTalk when they are signed in from their Android phone. This is despite being shown online on the chat lists. This however seems to be only part of the problem. Users on the Google Support forum have been complaining that users who are signed in on both the desktop and mobile phone see a more erratic behavior where the user’s activity from the mobile phone seems to go unnoticed. A user writes,
“If I’m logged in both Desktop and Phone, the behaviour is erratic. Usually when someone messages me I get the message on my Desktop. If I answer from my Desktop everything is fine, but it doesn’t show on my Phone. If I start answering on my Phone the other person will get my messages, but I don’t get any in either platform. Messages still show in the Gmail log of the chat. If I answer from the Desktop the conversation starts to flow again on this platform, while the Phone will still only show the messages I send from it and none of the other person’s messages or my own messages sent from Desktop like it used to do it before.”
Google has acknowledged the issue and is presently learned to be reproducing the bug at their end to find out the root cause. Expect a fix for the same in the next couple of days.