We are not quite sure when this was added to the Ovi store but we spotted an App called IM for Nokia - Chat on the go. Nokia's Ovi Chat will be refreshed to include this new IM ( instant messaging ) feature.

Instant messaging is provided via Ovi Chat which also works with Yahoo Messenger, Windows Live Messenger and Google Talk.

Once you've downloaded the Nokia IM App you can enjoy conversations across multiple IM communities, include an Avatar, setup your status and and receive notifications as they happen.

Having looked at the Nokia IM App download page it seems all Nokia phones can benefit from this and it can be  downloaded here.