I did seem to get my two instances of my number working on GrandStream
and ZyXel working ... but I have had the ZyXel off-line for a couple of days
pondering the lack of VMWI.

So its a nice simple setup with GS only behind a NAT connection.

When VMWI was introduced, my phone never lit,
but I would have a stutter tone
and the GS would blink green.

The last few days, I still get messages, but I can only tell
if I dial 123 to check or check my email notices.

Just wondering if this is true for everyone, or if its just me?
The only thing different I did for voicemail was turn off the
SMS messages.

I still wish I could assign SMS to a Group or have radio buttons
to add or remove VM/attachments/SMS for each group.