A leading UK law firm has dumped the mobile e-mail device over fears for the company's future - despite the fact that any BlackBerry blackout will only apply to the US, and the firm's chosen replacement also faces a patent dispute.

Darbys, a 150-strong firm of solicitors with headquarter in Oxford has moved 20 BlackBerry-using lawyers onto HP handhelds using Good Technology's mobile email software, and plans to move another 40 in the next few months.

"We don't know yet what the outcome (of the court case) will be," said IT chief Mike Warriner. "But any organisation facing a legal case like this is spending resources which can't be devoted to its customers or its product," he added.

Most people believe the chance of a shutdown is slight, given that RIM claims to have a patch would remove any dependence on the rival NTP patent, and also has a very strong financial incentive to do a deal.

Nevertheless, the chance of RIM being swallowed up by legal troubles was enough to cause the UK firm of lawyers to switch over, a process which it began last summer.

Darbys chose Good Technology, and reckons that the GoodLink software will work out cheaper than RIM, as well as providing improved security. The company also believes GoodLink is more standards based, and avoids the "single point of failure" involved when a solution comes from one vendor.

"With BlackBerry, the server administration overhead was very high," said Warriner. "GoodLink installation was simple and unobtrusive; an engineer came on site for a simple install, and we haven't needed to touch it since."

Warriner also rates Good's support for attachments. "In a recent meeting at our client's premises we needed to edit a document," he said. "Previously, we would have had to leave the client site and type up the changes, but with GoodLink, we were able to implement the edits immediately and email the document across to the client, all while sitting directly across from him."

There is, however, one downside. Good itself faces its own patent dispute, from yet another player in the sue-me world of mobile email. Visto is suing Good for allegedly infringing Visto's patents - Visto, which in its time has sued most of the other leaders in mobile email, itself settled with NTP in December.

Warriner is nonplussed by this legal action. " Visto's case is more to do with gaining column inches" he said.