Oracle Database Discussions

Hey, Ive some how locked my admin account for oracle, im 100% sure the username is system and password system, ive signed in using that heaps of times, also created an account username test and password test.

now for some reason when i try to sign into the system account it gives me the message "ERROR: ORA-28000: the account is locked", I can sign in with the test account but it doesn't have privileges to unlock the account system. The database is only running on my netbook and accessing it with localhost/xe, its oracle xe 10g. I think i may have locked myself out when I was running a php file just messing around with the wrong password a few times.

Is there anyway I can unlock this account or reconfigure oracle to reset the system password?

thanks :)