On Dec 5, 8:08 am, Patrick Plattes
...
> i had a problem with str.crypt - i got every time the same result. The
> problem is, that this method only use the first 8 characters of the string:
>
...

A little googling on 'C standard library crypt' led me to :
http://bama.ua.edu/cgi-bin/man-cgi?crypt_unix+5

It turns out the default crypt functionality only uses the first 8
chars, silently ignoring the rest.

Suggest looking into a "real" cryptographic lib.  Googling for 'ruby
crypt' gave up:
http://crypt.rubyforge.org/

cheers