Mobile operators will push the office deskphone aside with more advanced "push-to-talk" (PTT) features, claims Kodiak Networks. Analysts, however, dismiss the company's claims.

"The deskphone is obsolete," cried Bruce Lawler, vice president of business development at Kodiak. "You can't tell if the person is there, and you can't send a message immediately to them." Kodiak has launched products that use PTT to add intelligence to any mobile phone, aiming them at the office environment.

He's not convincing everyone. "It might work for smallish workgroups or smallish companies - that may just rely on cellular anyway - but it has no chance of competing with enterprise PBXs," said Dean Bubley, of Disruptive Analysis.

Push-to-talk has been successful in America but tends to be seen as a gimmick in Europe: a button lets the user treat the phone as a walkie-talkie, talking to one or more pre-defined users as long as the button is held down. Kodiak offers what it calls "advanced voice services" (AVS), additions to the push-to-talk feature list aimed at going beyond gimmickry. The company already offers the ability to move a PTT call to a normal two-way call, and has now added a bridge that can set up conference calls quickly from the handset, and a Voice Notes, an IM-like service that uses "presence" and users' existing voicemail boxes.

To persuade operators to build all this into normal cellphones, the company has put the software in a thin client that runs on the SIM, not the phone: SIMvantage, a version of its software will run on the Java Virtual Machines that are appearing in cellphone SIMs. "This lets operators sell AVS to their existing customer base," said Lawler.

The bridge sets up calls much like those available through conferencing services, "It supports up to 30 people, and the quality is as good as a conference service," said Lawler. "It opens up an opportunity for people who wouldn't normally do conferencing."

Voice Notes lets users check whether their buddies are available, before sending a message to one or more mailboxes. "It allows group communications," said Lawler. "Until now, the phone has been a one-to-one device. We make it a one-to-many device."

Despite Kodiak's confidence, analysts reckon that mobile phones will need more than PTT to take on the mighty deskphone - especially when most communications managers would rather move the other way, using Wi-Fi and cordless to reduce their dependence on mobile phones in the office.

"I'm deeply skeptical about everything related to PTT," said Bubley. PBXs are already owned by the enterprise, and have a long lifespan, he pointed out: "Are any handset manufacturers or operators likely to support a given handset for seven to ten years?" Landline calls are already much cheaper than mobiles, and PBXs are making them even cheaper with free VoIP calls.

Besides, the presence functions that Kodiak presents are already appearing in enterprise PBX-based systems, said Bubley, citing products like Siemens' Openscape. Intelligent PBX-based systems are also being integrated tightly with CRM and call-centre applications. It would be much harder to do this with PTT-based systems, said Bubley.

Although Kodiak supports the IP Multimedia Subsystem (IMS) standard, Bubley said its proprietary Real-Time Exchange system was a mixed blessing: "The good news is that it is less sensitive to latency on typical GPRS networks, as it's circuit-switched and not reliant on VoIP. The bad news is that it's non-standard and supported only patchily."

If the idea is so good, says Bubley, you might expect vendors that have both PBX and cellphone arms, such as Siemens, Alcatel, and Panasonic, to be offering it. They are not.