With the Express Modem and GeoPort, there is a time delay of 6 seconds between when a ring is detected and when you can issue a an "ATDT" command. The way to eliminate this would be to type "ATH1DT" instead of "ATDT". The "H1" forces the modem to go off-hook. Once off-hook, the "DT" command can be issued causing the modem to think it is the originator.
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