UC500.com

I am installing a UC520 with 3 PSTn lines in a Rotary Hunt group as bothway FXO lines.
I have set them to terminate on 3 dn's with the same number in a hunt group that appears on all the 7941 handsets on an overlay key.
This way all the phones can answer all the lines.
My problem is how to get these calls to go to a Night voicemail box.

I can assign a night mode access code which seems to change the system to night mode , but i dont know how to divert the common dn number to voicemail.

The alternative is to select the overlay dn line and just fwd all it to the voicemail pilot , but then the voicemail doesnt recognise the call because the overlay dn number is not a physical extension.

Is it possible to have a CUE mailbox without using a physical ext ?

this is the relevant portion of the cli so far
!
!
ephone-dn 31 dual-line
number 3001 no-reg primary
label 84102626
name PSTN
huntstop channel
no huntstop
preference 1
!
ephone-dn 32 dual-line
number 3001 no-reg primary
label 84102626
name PSTN
huntstop channel
no huntstop
preference 2
!
ephone-dn 33 dual-line
number 3001 no-reg primary
label 84102626
name PSTN
huntstop channel
preference 3
huntstop
!
voice-port 0/1/0
connection plar opx immediate 3001
!
voice-port 0/1/1
connection plar opx immediate 3001
!
voice-port 0/1/2
connection plar opx immediate 3001
!
!
ephone 5
button 1:10 2c31,32,33
!
ephone 6
button 1:11 2c31,32,33
!
ephone 7
button 1:12 2c31,32,33
!
ephone 8
button 1:13 2c31,32,33
!