i missed the end of this thread…
yes, MS in Packet Transfer Mode cannot be paged unless the Gs interface is present (NMO I) or the BSS is able to do the CS Paging Coordination by itself (BSC feature).
Some MS are however able to be paged during PTM without those mechanisms, because they are actually hearing the PCH from time to time (those MS are rare, AFAIK).
Gs interface is pretty difficult to configure, but it’s whole purpose is to allow MS to be paged during PTM. So it is not normal if it is not working. The best would be to trace the Gs interface and verify that pagings are going through.
There are 3GPP specs that describe Gs interface, you should have a read (I must admit : I didn’t). They might explain what should be expected from SGSN and MSC, that could help configuring everything properly.
TS 23.060-GPRS Service Description
TS 29.016-Gs Interface
TS 29.018-Gs interface layer 3
I would be happy to know how you fixed this issue.
Have fun 😉