That's a good one. On a VG248 it is a MWI option that you can choose. Stutter, Lamp, Stutter and lamp, etc.
But it is not there for a vg224 and never had that requested. I did on a VG248 and it worked.
Let us know what you find out.
By the way is there a reason for SCCP vs MGCP? I have found that in most cases you lose some analog functionality with skinny. I had to revert to MGCP in several cases so I warn the customers if they insist on SCCP. However in your case I don't think that is the issue as it is not an option in SCCP or MGCP mode.