Encyption and Decrption

[Anon]

Can anyone help me to encrypt and decrypt a string say a password without the complicated Encyption techinques( i mean the Encryption Library of functions to be installed separately).

We are using PHP 4.0.
All i want is encrypt and decrypt a password with just string manipulation. I tried using ord and chr functions, but failed to do so.

Any help ?
Thanks.
Bijal.

[Anon]

Dear Sir,
you can use the next character, A encripted to B and B encripted to C....and so on..so that the decription is the previous character.