Research in Motion has filed a lawsuit in a United States federal court, claiming that Samsung's Blackjack violates a trademark held by RIM.

A few weeks ago, Cingular Wireless began offering the Samsung BlackJack, a Windows Mobile Smartphone (pictured at left). RIM believes that the name of this device is too close to the name it has trademarked for its long-running line of smartphones, called BlackBerries.

RIM is claiming that the BlackJack "constitutes false designation of origin, unfair competition, and trademark dilution".

There can be little doubt that in additional to its similar name, the BlackJack has a similar form factor to BlackBerry models and performs similar functions. Obviously, though, it will be up to the court to decide if the names are similar enough to qualify as trademark infringement.

This lawsuit was filed last week in a federal court in Los Angeles , Calif., because, despite the fact that RIM and Samsung are based in different countries, the BlackJack is only available in the U.S.

Further details will only be available as this court case progresses.