[Asterisk-Dev] Problems with disconnect supervision in X1000P

[Jorge Merlino]

Hello

We have a X100P card and have just asked our telco to enable disconnect 
supervision in the line (or so we think).
We have checked the line voltage and saw that the line reverses polarity 
  just before the first ring (from +45 to -45 approx.), the voltage 
falls to -8 when asterisk answers the line and it is reversed again when 
the remote party hangs up (from -8 to +8 approx.) but the X1000P does 
not disconnect the channel. This service is called incoming polarity 
reversal by our telco.

Is this a problem with the card or the card expects as disconnect 
supervision is something different?
In the last case could anybody give me a hint about how to make the card 
disconnect on hangup?

Thanks in advance,
	Jorge