Multiple certificates

Phil,

In the proposed XCBF CS, "certs" has type CertificateSet, which is
defined as:

	CertificateSet ::= OCTET STRING

Line 1523 says:  "Any combination of X9.68 domain certificates, X.509
certificates and attribute certificates may be included in the
CertificateSet type in any order."

It has just occurred to me that the text does not say how to combine
multiple certificates in a single OCTET STRING.  

Should they be simply concatenated?

Alessandro