Judge refuses to enforce disputed patent deal, may ban BlackBerry sales; RIM shares tumble.

BlackBerry maker Research In Motion Ltd. was dealt another legal setback in a key patent infringement case on Wednesday, raising pressure to settle or face a possible shutdown of its U.S. mobile e-mail service.

U.S. District Judge James Spencer denied a request by Research In Motion to enforce the terms of a disputed $450 million settlement reached earlier this year with patent holding company NTP Inc.

Now the judge will set up a hearing on whether RIM can keep selling or importing its BlackBerry hardware and software in the United States.

RIM (down $3.79 to $61.13, Research) stock, halted for the news, tumbled after reopening, sliding about 7 percent on Nasdaq and in Toronto.

It will be interesting to see how other PDA manufacturers react to this…continue reading courtesy of cnn.com