Sony Ericsson's displeasure is nothing new to Clearwire, according to the complaint. Sony Ericsson said it has already challenged trademark applications by Clearwire for versions of its green logo, and that it held talks with Clearwire for several months last year that led to Clearwire discontinuing one version of its logo. But Clearwire's latest mark, introduced without a word of warning, apparently set off Sony Ericsson.

"Clearwire has endeavored to create marks that are confusingly similar to Sony Ericsson's marks," the complaint said.

The suit accuses Clearwire of both trademark and copyright infringement, as well as unfair competition under the laws of both the U.S. and the state of Georgia.

Clearwire spokesman Mike DiGioia said the company would not comment on the suit.

The IDG News Service