asterisk users - Mar 2009 - Strange voicemail problem when call forwarding off local PBX

Hi All,

I just experienced a weird issue and though I'd share.

I have a pretty standard business PBX setup for a business customer,
local extensions, Linksys phones, call comes in and rings local
extension
exten => 101,1,Dial(SIP/101,20,tr)
the physical phone has call forward enabled to the users home, Time
Warner residential line service.

Intermittently all seems to work except when the home line voicemail
picks up.  You hear the users home voicemail greeting, but
sporadically, instead of hearing a beep after the greeting is
finished, the local PBX initiates a transfer.

Sometimes you do hear the beep from the residential voicemail and can
leave a voicemail.  So after a few minutes of pondering the
possibilities, I came to the conclusion that the residential voicemail
service 'beep' was triggering the local PBX transfer function, but not
all the time.

I have not come across this before and I have a lot of customers that
transfer calls out to cell phones and home lines, other voicemail
services.

The simple solutions was to disable 't' option in the dial string when
calling the local PBX extension 101.  The customer uses the phone
txfer softkey anyway so no disruption of local function when the user
is in the office.

Hope this helps.

JR
-- 
JR Richardson
Engineering for the Masses