Today's enterprise IM market is worth an estimated $100 million a year, Gartner estimates-a modest sum for the software world. But as major players like Sprint and AOL roll out their own enterprise IM products, Gartner predicts the market will grow at least 50 percent annually over the next three or four years.

Meanwhile, companies such as Foster City, CA-based Facetime, Chicago-based Imici, San Francisco-based Messagevine, and Denver, CO-based Jabber are competing to provide the mortar to patch these disparate IM languages together into a single network.

But not everyone is convinced that the patchwork will hold up. "These gateway systems are going to be strung together with spit and bailing wire," says Gartner's Batchelder. "It won't be reliable as a synchronous communication system." Unlike e-mail, Batchelder says, IM has no "safety net," queues into which undelivered messages can go when there's a breakdown somewhere in the network. "No one's ever been able to build a real-time messaging system out of gateways," he says. "To do a real time messaging system you need an overarching network and an infrastructure such as AOL, MSN, and Yahoo! that can be commonly used by all the parties that want to traffic over it."

Cordant's Aggarwal and IMlogic's deSouza both admit that gateways will likely turn out to be a temporary fix. The ultimate solution, they believe, will come not from a single network provider like AOL but from a coalition of providers signing on to a single protocol, such as the Session Initiation Protocol, which is being developed by the Internet Engineering Task Force. "There's too much investment in multiple protocols from the different parties," says Aggarwal. "To surrender to any one network means the others all go out of business."