U.K.-based Ubiquity today announced that AT&T will use its SIP application server in its trial of advanced Voice over IP applications.

Ubiquity has already announced similar deployment by Bell Canada, and said today its servers are in use by major providers in both Europe and Asia.

“We are very excited,” said John Hart, vice president of product line management for Ubiquity. “We have, by the signing of this agreement, been picked as the platform on which AT&T will trial their new applications.”

This choice follows a laboratory “bake-off” that pitted Ubiquity against competing SIP application servers, Hart said.

“If you take a look at the world economy, the G8, we as a company are very fortunate to work with the four of the largest telephone operators in the world, which represent the top four G-8 countries,” he said. “We are extremely well positioned to now go into full production with their major providers.”

The trial agreements don’t represent contracts for full deployment, he acknowledged, but are one step in the direction.

“It puts us into a very strong position to go to full production for deployment,” Hart said. “They are paying for the new appls being delivered on our platforms.”

Those applications include multipoint conference calling, Instant Message sharing, picture sharing, music and video sharing and more.