чтобы допустим при наборе телефонного номера - шлюз автоматически ставил впереди номера какую-либо цифру, на подобе команды set tcid 0 dial_in plar 9 в 104 шлюзе...

в 1104 что-либо подобное есть?

Стр. 27 мануала:
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sysconf
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- drule: This command only works while 2nddial is off. When user would like to make an outgoing call or receive an incoming call shortly, it is necessary to set the following three commands belonged to drule. ● drop: drop the dial digit. ● insert: insert the dial digit ● filter: filter the dial digit.
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1. out: Through DVG-1104TH to dial out to another Gateway’s e164 number. When making an outgoing call, it is necessary to set three commands in order, filter, insert then drop.
Example: sysconf –drule out_filter 002886 out_insert 0 out_drop 02