When adding a new entry, if you you don't "OK" the dialog box before the database auto locks, then you loose what you've started. The 'Add Entry' box is greyed out, there is no way (that I can find) of unlocking the database. Clicking the X on the dialog box bar, destroys the dialog (loosing it's contents) but you regain the ability to unlock the database.
For instance I start adding an entry. I generate a password. I use the password to open a new account. I forget to finish the 'add entry' and it times out. I kill the 'Add Entry' dialog box to unlock the database. But I've now lost my password as the clipboard was cleared too.