Dial patterns consist of the following characters only:
0 1 2 3 4 5 6 7 8 9 X Z N | . ! [ ] , – +
X matches any digit from 0 – 9
Z matches any digit from 1 – 9
N matches any digit from 2 – 9
| separates a dialing prefix from numbers dialed, e.g. 123|4567 would match the dialed number 1234567, but would only send 4567 on to the trunks.
. matches one or more digits, e.g. 0. would match a 0 followed by one or more digits
! provides legacy overlap dialing support and matches as soon as it can unambiguously, without waiting for the dialing to complete, allowing subsequent digits to be transferred directly to the trunk (only supported on PRI channels).
[ ] allows a collection of digits to be matched, e.g.  would match 7, 8 and 9
+ in conjunction with | allows insertion of digits into the dial string, e.g. to change 0114567890 to 27114567890 use dial rule ’27+0|X.’ in the Dial Rules section on the trunk from the Advanced menu