RIM on Christmas published a patent filing that hints at an attempt to overcome some of the size limitations of the BlackBerry Pearl and Pearl Flip. Describing the design as an "appearance adaptable" keypad, the method would have the appearance of a normal BlackBerry number pad but contain hinged sections that fold out past the normal dimensions of the phone to provide a larger SureType keyboard with two letters each.

The design would be more comfortable for e-mail and texting without forcing users to opt for a larger overall phone in the process, RIM explains.

While an important step, the filing doesn't necessarily point to a production device and isn't forecast as part of any known 2009 releases, with a just-leaked Rogers roadmap so far only pointing to a 3G Pearl Flip as part of RIM's plans for SureType. [via Cellpassion]