Verizon Business, a unit of Verizon Communications Inc., was created in January out of Verizon's merger with MCI. The new Hosted Secure Instant Messaging Service builds on an e-mail service launched by MCI in April 2005, according to Rick Dyer, director of IT solutions product management at Verizon.

Dyer said IT managers need such a service to add security to instant messaging applications that users are increasingly demanding. Plus, a hosted service will reduce the headaches of administering IM, he said.

"IM is already in the enterprise, and IT managers know that if you shut off public IM, it will bring an outcry for those who have gotten used to it," Dyer said. "So we're trying to provide a service so that IM meets their corporate guidelines and prevents backdoor security holes."

The service has two options, and customers can have either or both. The services are available now in North America.

One option, Enterprise Instant Messaging, uses Microsoft Office Communicator 2005 software and encrypts IM chats between users. It also integrates with Microsoft Outlook to improve efficiency for users. Enterprise IM starts at US$5.95 per user per month, with a 25-user minimum, Dyer said.