With the X500Principal class, it is possible to obtain a RFC 2253 compliant DN. 

Perhaps it would be useful to introduce a convenience method to service/authz
programmers (S.Meder suggests to add it to the JAAS subject) and maybe even to
eventually introduce this as an available way to represent DNs in gridmap files
etc.


import javax.security.auth.x500.X500Principal

X509Certificate userx509 = null;

// get userx509 

X500Principal userx500 = userx509.getIssuerX500Principal();
subjectName = userx500.getName();