Hi,
I use Linksys SPAs and I was never able to get **ext pickup to work within a ring group (although it worked fine for a single extension).
This was a problem for me because my extension wouldn't start ringing again when it became free. See my post from the time.
I always get an invalid number when trying to use call pickup on my spa303 is there something that needs to be added to the dialplan on the phone to make this happen?