I just got stuck with the same problem and found a solution. So, I may as well share it ..
The password is a md5 hash.
ex: newpass = e6053eb8d35e02ae40beeeacef203c1a
Access your mysql table "tbl_users", find your user name and replace the "u_pass" with your md5 hash.
If u_name = admin and u_pass = e6053eb8d35e02ae40beeeacef203c1a
Your username will be "admin" and password "newpass"