When the U.S. Supreme court rejected Research In Motion's appeal last week, the BlackBerry maker's patent battle returned to a lower court. Today, U.S. District Court judge James Spencer set Wednesday February 24 as the date to hear arguments about a possible injunction in the five-year old patent infringement case.

At stake is RIM's ability to do business in the U.S.: The judge could stop RIM from selling its wares in this country. Or, as many analysts think, use the threat of an injunction as way to force the Canadian company to settle with patent-holding company and litigant NTP. A settlement would cost the push-e-mail vendor hundreds of millions, if not a billion dollars or more.

A previously agreed upon $450 million deal between NTP and RIM fell apart last year, leading to next month's show down. The two sides haven’t come close a resolution since. Millions of ‘crackberry’ addicts and IT managers are nervous about what’s going to happen next.

Meanwhile, the United States Patent and Trademark Office (USPTO) continues to reject (in a preliminary mode) NTP patents left and right, leaving some to wonder whether the Virginia-based company has two legs left to stand on. Final rulings on the patents may not arrive for weeks, however; most likely after the judge rules.

Should RIM be forced to cease U.S. operations, NTP says it would grant a 30-day grace period to allow BlackBerry users to change services. Government users and first responders would be exempt from a shutdown.

RIM says it has technology to "workaround" the patents in question should the court issue the injunction, an idea that has met some skepticism. The technical hurdles could significant and there’s no way to know for sure if it’ll keep RIM out of hot water.