The patent infringement spat between Research in Motion (RIMM: Quote, Company Info) and Good Technology intensified Thursday with yet another lawsuit related to the user interface of RIM's BlackBerry handheld devices.

The Ontario, Canada-based RIM, which is already embroiled in litigation with Good, is again alleging patent infringement and is seeking injunctive relief and unspecified monetary damages.

Good Technology, which goes head-to-head with RIM in the wireless software market, set the legal tussle off in May when it sued RIM arguing that the patent on single unified e-mail claimed by RIM was not valid.

In its latest response, RIM warned it would continue to keep track of Good's technology "to determine whether any other rights are violated," a hint that more suits may be coming.