However, critics say consumers are still cut off by AOL's refusal to embrace interoperability.

AOL says the trial with IBM that began this week is part of the company's ongoing effort to explore interoperability with third-party IM systems "in a secure and reliable manner."

A group called IM Unified -- companies including Microsoft , Yahoo! AT&T, Excite@Home, Odigo and other IM players aligned to force interoperability -- complains that AOL continues to drag its feet and is leaving consumers separated by different IM systems.

Odigo vice president of sales and marketing Alex Diamandis told NewsFactor Network the test is the "bare minimum" for AOL to live up to requirements imposed by federal regulators when they approved AOL's US$106 billion merger with old-media titan Time Warner earlier this year.

"They're not going out of their way to satisfy the FCC regulations, that's for sure," Diamandis said. "They're doing the minimum they have to."

Test Message

AOL says the trial will allow its AOL Instant Messenger (AIM) and IBM's Lotus Sametime to communicate on a server -to-server basis using a protocol called Session Initiation Protocol for Instant Messaging and Presence Leveraging (SIMPLE), currently under consideration by the Internet Engineering Task Force (IETF).

AOL says the test will help it examine how to enable interoperability with other systems using the new SIMPLE protocol, which is also backed by Microsoft and IM Unified.

"AOL is committed to achieving IM interoperability in a way that protects consumers' system performance, privacy and security, and this trial will help us better understand technically how IM interoperability might work," said AOL president of interactive properties Donn Davis.

Marketing Move?

The AOL and IBM messaging systems are reportedly working together, but those behind the competing IM systems complain that the two companies' IM relationship stems back to 1999 and the trial is more of a marketing move than an effort toward interoperability.

"The test will be with a partner that is already working with AOL and that is primarily used for commercial purposes," Excite@Home spokeswoman Estela Mendoza told NewsFactor.

Diamandis said AOL's existing relationship with IBM and the trial show AOL's need to gain presence in the enterprise IM market.

"It's certainly a marketing-slash-business move," he said.

Still A Step Forward

Despite their complaints, members of IM Unified expressed some encouragement that AOL is testing interoperability, considering the company's past resistance, which AOL contends is based on a desire for security and privacy.

"I'm encouraged to see AOL doing anything, frankly," Diamandis said. "We're happy to see AOL moving forward even if it's with IBM, who they've worked with on Sametime since 1999."

Lotus Software general manager Al Zollar called the trial a significant step toward leveraging the widespread use of AIM and real-time, enterprise collaboration, saying the endeavor will "potentially create larger opportunities for IM interoperability."

Common Protocol

While the IETF has not rendered a decision on the SIMPLE protocol being put to use in AOL's test with IBM, the interoperable standard does have the backing of both AOL and Microsoft, according to Diamandis.

"Whether it's optimal or not, technology that is being backed by those two will certainly drive people to support it," he told NewsFactor. "Still, supporting SIMPLE is one thing; being interoperable is another. We'll see how it plays out."