Pattern lock doesn't secure data.

[banden]

Pattern based screen lock doesn't protect data. Very easy to bypass.

Simply call your phone. The whole time you are on a call the phone can be completely navigated including reading emails and SMS... just hit the back button when in the phone call screen.

I know I've said it before, but get your phone on either an Active Sync server or on Mobile Defense (BETA) so that you can remotely wipe your phone.

EDIT: This is a Motorola Droid only issue (2.0 based)