Nortel's bankruptcy filing could spell trouble for its unified communications deal with Microsoft.

In November, the two companies said the four-year Innovative Communications Alliance (ICA) formed in 2006 was solid and intact. ICA is a plan to jointly develop, sell and roll out unified communications and VoIP technology to corporate customers.

November's assurances came after Nortel had announced a US$3.4 billion loss. With Wednesday's filing for Chapter 11 bankruptcy protection in the United States, Canada and Europe, the longevity of the deal is again called into question.

"Bankruptcy does not mean going out of business, but Nortel is fighting for its life," says Zeus Kerravala, an analyst with the Yankee Group.

From the partnership perspective, Kerravala says bankruptcy makes it harder to get things done. "If I am Microsoft and I want to get Nortel to invest in creating a new product is that still a viable option?"

Kerravala also says Nortel's largest install base is its VoIP customers and he predicted the company's competitors would jump at the chance to steal those accounts. "The faster Nortel can touch those customers and help them understand where investments will be the better it will be for Nortel. The next 90 days are critical."

How Nortel reacts could dictate how its partnership with Microsoft evolves.

Microsoft said it is waiting for more information before it can evaluate the fallout. "All ICA offerings are currently available to customers and no changes are planned at this time," said a company spokesman. "We are not in the position to assess the impact of the ICA until we understand Nortel's plans."

The ICA deal is set to expire in 2010 and may do just that before Nortel can emerge from bankruptcy and get going again. Or the bankruptcy could turn everything upside down depending on what actions a bankruptcy court forces upon Nortel.

Company CEO Mike Zafirovski said in a public letter Wednesday to "Friends of Nortel" that filing for bankruptcy protection in the United States will allow the company to reorganise and undertake a comprehensive business and financial restructuring.

Nortel late last year produced another ICA integration when it introduced Nortel Secure Network Access 2.0, which marries its Secure Network Access Switches 4050 and 4070 and Microsoft's Network Access Protection (NAP), which is technology for verifying that a client desktop is secure before letting it onto a network..

At that time, Ruchi Prasad, vice president and general manager of ICA for Nortel, said, "We are committed to ICA."