Hola/Hallo/Hello Scott!
 AH>> As it seems, line and phone connectors are connected
 AH>> "in parallel" i.e. pins a-a1 b-b1 are _not_
 AH>> disconnected in off hook state...
 AH>> Is there a way out ? For example an electronic patch or
 AH>> even a software switch ???
If you have an external SupraFaxmodem you could connect a transistor to the 
OH LED and drive a relais.
Saludos/Groetjes/Bye, 
 Rene
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