America Online on Tuesday said it would launch a new pay service for making VoIP calls through its AIM client starting October 4. No AOL subscription will be required to use the service, and current subscribers of AOL's Internet Phone service will receive the upgrade automatically.

The company claims that consumers could save up to 40 percent over monthly landline phone bills by using the service, dubbed "TotalTalk."

AOL's TotalTalk will allow for free PC-to-PC calls, as well as PC-to-phone calls for which the user will be charged. The PC-to-phone capability will be offered through a preview edition of the AOL Triton client to be made available later this week.

Tuesday's announcement heralds the beginning of what could shape up to be a fierce VoIP battle among the leading instant messaging clients.

MSN is separately planning to enhance its VoIP offerings within the next several months, further integrating calling capabilities with MSN Messenger. Google has included PC-to-PC calling within its new IM Google Talk client. Yahoo also recently upgraded its Messenger client with the same feature.

TotalTalk services include call waiting, caller ID, star codes, voicemail, and three-way calling. 911 emergency calling is also supported, however AOL warns that the service works differently from traditional 911, and a user needs to be in their home location.

At launch, AOL will offer three plans: a local plan, an unlimited calling plan for the United States and Canada, and a global calling plan that offers discounts on international calls. The prices for each plan will be $18.99, $29.99 and $34.99 USD per month, respectively.

Those wishing to learn more about the service can visit the TotalTalk Web site.