An encrypted password is just the real password scrambled and changed. It can be cracked with a password cracked and a word file. A shadowed password hides the encrypted password somewhere else other than the etc. dir.
A shadowed password is a cover for the real password file. It shows that the real password is hidden somewhere else. Cracking a shadowed password file is impossible. Assuming that you got the password file via anonymous ftp. You should try connecting to port 25 and doing the sendmail bug.