Russ,
I have three other minor comments:
1) Sec 6.2.3, "mlKeyId" was replaced by "mlid".
2) Sec 9.1, the definition for the originatorInfo field indicates that it
may contain user keying material (UKMs), as defined in Section 6.1.
However, UKMs are not contained in the originatorInfo field, but instead
are contained in the KeyAgreeRecipientInfo field defined in Sec 6.2.2.
3) Sec 9.1, the last sentence indicates that useful attribute types are
defined in Section 11. You should probably indicate that of the attributes
defined in Section 11, none currently apply for unauthenticatedAttributes.
Francois Rousseau