Using "Security measurement" as a reason, AOL locked their instat messaging network from other multi connect messager like Trillian. Trillian is an IM client that conects to various messaging network like ICQ and MSN.

A Trillian users Mike Cicciarelli said "AOL is being selfish" and the reason why people dont use AOL instant messager client is because of the Adsware where it display advertising on the bottom of the messaging software.

Trillian has released another version of it's messager to keep up with the changes AOL made to their messaging network.

Michael Gartenberg, a research director at Jupiter Media Metrix, called AOL's practice "predatory," but he said at least the media behemoth is consistent in blocking both large and small companies from accessing its system.

"There are no technical reasons they can't open up IM, but there are a lot of business reasons not to," Gartenberg said. "They're not going to unless they're forced to."