When entering your password incorrectly the device eventually prompts you to enter 'blackberry'. I assume that this is done for the exact reason the the OP experienced (faulty keyboard or keys pressed while in pocket).

Just as an example... I get 10 attempts to unlock my BlackBerry before its wiped. Before attempt #6, #9, and #10 I have to type 'blackberry'. Starting with attempt #6 I also see the actual characters I am typing (instead of ****). In addition, before attempt #10 I have to acknowledge that this is the last attempt before the device is wiped.