PasswordSafe Linux v0.3 3839 beta on Linux Mint 9
Set security options to lock on minimise (minimize) & on workstation lock.
A) Minimise using minimise button, or close button to minimise to system tray, then restore & password is not asked for.
B) Lock screen, then unlock - PasswordSafe is still open & does not require password to access.
Note, lock after 10 minutes idle setting does work okay.