[Asterisk-bsd] How to disable DND feature key in Polycom Phone

[Farooq Ahmed]

Hi
We have polycom 430,501 and 301 phones. Our customer does not need DND feature in any form. 
I can disable this feature from asterisk server but How can i disable this feature on phones. In the 
sip configuration file i found the parameter that change the phone behaviour during DND from busy 
to normal but still if the phone is in dnd mode the phone ringer would be off which is unacceptable.
Any idea regarding this.
Regards
Farooq

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