@Thomas Tempelmann is correct. What I have done is encrypt the password with something that requires a decryption key (blowfish/twofish are examples). Then did something like (the pseudo code below)
password = TwoFishDescryption( kEncryptionKey, DecodeHEX( kEncryptedPassword ) )where kEncryptedPassword is the encrypted password stored as a constant. Now it cant be changed unless you recompile the application. And kEncryptionKey is the key (password) to decode the password
This method has allowed me to (mostly/semi) securely store a password within the application and make sure that the client cant mess with it (much).