crypt()

Is there anyway to make crypt() behave like md5() and give the same results for the same string? All of the passwords for the db I am using had crpyt() applied to them before they were entered in the db. How do I then verify that passwords match? I just did this: $test=crypt('test'); print $test. "<br>"; $test2=crypt('test'); print $test2. "<br>"; and it printed out two completely different strings. I saw in the functions list it was talking about salt but I am not sure what that means. Thanks, Eddie