XF 1.4 Fixed: Password Error On Registration

I'm using Xen 1.4.2 and a visitor send me a message on facebook saying: I can't register ur site coz it gives error about password.

I checked it and got the same error. When u fill the form and click the register button, a message window appers and says:

1. Password is at least 5 characters long.
2. Password must have one or more numerical digits.

As u guess, the pass. I entered was longer than 5 ch. and had numbers in it.

Is there a problem with the version or u know anything to fix this issue?

Thanks 4 ur help.