T46G unable to stop spamers ghost calls

[mdrago]

Hi, using T46G FW 28.72.0.45

I'm receiving constant spamer / ghost calls, right now from extension '105' which don't exists on the PBX.
As noted on other threads, these calls came directly from the internet to my home router IP address, not passing though the PBX.

I tried the suggestions on http://forum.yealink.com/forum/showthread.php?tid=942 that is "Action URI allow IP List" = <PBX public IP address> and "Allow IP Call" = disabled

I also set "Local Anonymous" to "Off" and "Anonnymous Call Rejection" to "On" in the "account -> Basic" tab.

As a last resort, in "Account -> Advanced" I tried to change the "Local SIP Port" to 5071 but it WONT SAVE THE CHANGES!

The only thing I want to know is how to tell the phone to only accept call FROM THE PBX SERVER, and I would like to do this from the web interface, not from a CFG file as stated on http://forum.yealink.com/forum/showthread.php?tid=1692

Sorry for the caps, I'm really frustrated and seconds away to trow the phone out the window.