The Dulles, Va., company has launched Open AIM, a free developer kit that allows the creation of plug-ins, mashups and third-party applications that connect to AOL's 63 million AIM users.

The Open AIM program gives smaller companies, Web communities and developers access to the code base of AIM Triton, AOL's next-generation IM client, and the ability to create their own versions of the AIM service.

"What this means is that literally anyone can build a plug-in for AIM, an AIM client or a mashup to sell to consumers. They can even put advertising around what they create," said Jamie Odell, director of product management for AIM.

Mashups, which are popular in the Web 2.0 realm, are Web sites or Web applications that combine content from several sources into a seamlessly integrated experience. Several big-name companies, including Amazon.com, eBay, Google, Yahoo and Skype, have expanded their footprint by experimenting with mashups and giving developers free access to their databases.

In an interview with eWEEK, Odell said the AIM Pro client recently rolled out for business users is the first high-end example of a custom AIM client that can be created with the API (application programming interface) released with Open AIM.

Justin Uberti, chief architect of AIM, said the Open AIM initiative gives developers access to the entire network of users, including those running the proprietary AOL member service, the AIM and ICQ services, and Apple's iChat service, which is hosted by AOL.

It also includes access to enterprise IM users via AOL's partnerships with the Microsoft Live Communications Server, IBM Lotus Sametime 7.0, Reuters 5.0 Communicator, Antepo, Parlano, Omnipod and Jabber.

Uberti said the new developer clients will be hosted by AOL, meaning that users will be able to sign on using their existing AIM screen names and passwords. Separate licensing deals are required for businesses that want to use their own user name space.

A key part of the initiative, Uberti stressed, is opening up access in a secure way. He said the Open AIM program will encrypt all communications between the user's PC and the AIM network using SSL (Secure Sockets Layer), regardless of whether or not the user has a digital certificate.

It will also support digital certificates to offer additional security for peer-to-peer operations and to guarantee user identity.

Uberti said Open AIM will facilitate up to 250,000 log-ins per day or 2 million log-ins per month.