Are you kidding me? You are limiting passwords to 12 characters? And you consider this sufficient security? Sounds to me like you're storing the passwords in plaintext.
No, it's encrypted.. and B: we were thinking that people might one day want to use it for their mobile phones... so I have no idea what kind of phone you use.. but I'd rather not type in a 30 character password.
For a cellphone, it may be easier to type a 20 character numeric password (66.4 bits of entropy if random). A 12 character password can't really have over 72 bits of entropy. Computers are getting stupidly fast these days. Anything with less than 64 bits of entropy is likely insecure. After 128 bits you are probably safe as long as the storage mechanism has no underlying weakness.