Question to XKMS and XBulk

Hi everybody,
 
I am not really an expert with XML but I am working on a mechanism for
the exchange of certificate managment information, i. e. certification
reply and certification respons. Because we have to do this for quite a
lot of certificates we are to use XBulk.
This works quite wunderful for p10 requests and x.509 certs.
The issue is, that we do not produce only x.509 certificates but also
card verifiable certificates according to ISO/IEC 7816-8:2004 and CEN
CWA 14890-1.
The underlying request is in p10 form, so we can use existing schemas. 
 
But what about cv certificates?
 
Is it possible to but tem into an existing structure/schema like
X509Data?
Or do we have to extend the XBulk-definition and, if so, how will this
be done?
 
Best regards
 
Thomas Beckmann