[asterisk-users] all call forward

[unplug]

Hi,
  How can I set all call forward to another number?  I have tried to
change the exten but it doesn't change.

original exten is 7654321
exten => s,1,Set(EXTEN=1234567)
exten => s,2,NoOp(${EXTEN})

The result is 7654321.

Is it possible to change the value of ${EXTEN}?  Or does it have any
better way to implement to the all call forward feature?