just do a rot13, and get some little obfu, ie dont call it $passwd nor its (de)cypher function &decypher...
Or/and write the password in hexa instead of Ascii, or mix everything...
Eventually, put this pass and decypher code in a file called ".. " (with the trailing space) which will be called from your script.
Mixing all of this can be really enough for a beginner admin...

Eventually, use some Acme::Bleach or Acme::Morse or stuff like that...

All this is useless against a smart user but should really do the job but remember: if you have a
decypher($passwd);
They will immediately do a
print decypher($passwd);


At least I would ^^

P!