Research in Motion (RIM), maker of the Blackberry, has won a stay of execution after a U.S. judge opted not to impose an immediate injunction closing its service.

In a legal dispute with technology firm NTP, which claims the Blackberry has infringed its patents, the popular e-mail device could have been forced to shut down its mobile e-mail service in the US immediately.

Judge James Spencer said he would consider an injunction in the future. He said that RIM had infringed NTP's patents and that he would rule on an injunction as "soon as reasonably possible" but did not indicate when he might do so.

RIM announced a few weeks ago it has developped a software patch that would enable its handheld e-mail devices to work even if the ruling goes against it ( see workaround).

Legal experts said they expected the judge would encourage both sides to settle the dispute out of court.

Canada-based RIM said recently that it was negotiating with NTP, but described the U.S. firm's offer to license the disputed technology as "untenable".

The battle between the two companies dates back to 2002, when patent-holding company NTP successfully sued RIM in a lower court.

The two firms agreed a tentative settlement last year but the agreement subsequently collapsed.

Earlier this month, the U.S. government asked a federal judge to hold off from a possible shutdown of the Blackberry service, because of the system's popularity among key government employees. The Balckberry is said to be used by more than 3 million people in the U.S.