Is there a way to modify an environment variable that gets passed to a CGI?  For example, I'm doing Kerberos authentication and the realm gets appended to the REMOTE_USER variable, e.g., REMOTE_USER= username@MYCOMPANY.COM.  I just want username and not the realm.  I would prefer not to do this in the CGI because the CGIs are already written (legacy in house application).

TIA.