asterisk users - Feb 2005 - problems detecting hangup events

Im having problems with asterisk detecting when a calling party through a
PSTN line has hung up. It takes 10 sec for it to finally detect.

Im revieving my service through telus residential line.

i have a SPA-3000 and a wildcard fxo, both behave identical. Ive checked
voltages, everething seems correct.

is this a problem with my setup?
is this a telus problem?

any suggestions would be appreciated as this is causing havoc with
voicemail.. all extensions are recieving blank voice mail messages because
of this.

thanks..

Vince