You should be able to right click and copy the existing 75:MATH LD ARS table, then right click and paste the copy. Rename it MATH Intl. The ARS table number will be added automatically.
Go the the "0N  NSi"Mainnumber"  Barred  5" entry, change the Number portion to 0NSi"Mainnumber" (Notice the 0 in front of the N  you need to send it out to the phone line, and just N will strip that off). Change the Barred to Dial 3K1
Same with the User Rights, copy and paste Math LD, rename it MATH Intl. Go to the Short Codes tab, you should find the entry 8N / Dial / N / 75:MATH LD. Change the 75:MATH LD to your new ARS table XX:MATH Intl
So a User in the MATH LD User Rights, dialing 801133160306031 will send 01133160306031 go to the MATH LD ARS table, where anything beginning with 0 will be Barred.
A User in the MATH Intl User Rights, dialing 801133160306031 will send 01133160306031 to the MATH Intl ARS table, where 0N matches, which sends 01133160306031 out to the line
