I believe the , and ; characters are more about the phone than the
carrier. The "," character tells the phone to wait 2 seconds
continuing with dialing additional digits. The ; character makes the
phone wait until you actually press a button on the screen to trigger
it to continue with the dial string. So basically, I don't think the
phone ever sends any characters to the carrier beyond 0-9, # and *
(which I've known a conference bridge or two that uses * instead of
#).
Honestly, I'm not sure those characters need to actually make it into
application exclude list. If when selecting a contact with a long
dial string, only the actual phone number makes it on the list, and
the application will bypass GV when it sees the main number dialed,
regardless of the characters following in the dial string, I think
that would be sufficient to make the feature work.
I suppose matching the entire dial string might make it more flexible,
although I'm not sure how often you'd want to use GV to call an
extension of a particular main number, and not use it for a different
extension.
Obviously you will know better which way is easier to implement and
which will be more useful to your customers :)