CORBA35 — use of the SSN number in the 1988 TCAP version

As far as I can see when using the 1988 TCAP version the submission
does not seems to handle the case where the subsystem number (SSN) is
used to seperate between several TC-User protcols per GT (typically
protocols from different vendors). The naming tree proposed for the
1988 TCAP protocol can only store one TC-User protocol per GT, that is
only one DefAc per GT can be stored (see section 4.3.1.1 in the
proposal).

The use of the SSN number for this purpose is explained in chapter
4.2.3 in the second paragraph in the ITU Recommendation Q.775.

It should be easy to fix this as one only have to use the same naming
tree structure proposed for the 1993 TCAP version in these cases.