You may be able to do this using CLI on UC 500 (only for analog FXO trunks). Create a pots dial-peer with destination pattern matching the entire speed-dial number. Add the prefix command to this dial-peer with a "," between digits as required. I haven't tested this, but it should work - give it a try.
The control for adding pauses lies at the telephony interfaces that provide a transition from IP network to PSTN network. If you need to add pauses for multiple speed-dials, you will need to create a unique POTS dial-peer for each one. Below is an example of a POTS dial-peer (for FXO port), that will add pauses when dialing out.
dial-peer voice 5100 pots destination-pattern 914085551234 port 0/1/0 prefix 1,4,0,8,5,5,5,1,2,3,4
In the above dial-peer, the PSTN access-code 9 will be stripped off and pause will be inserted between each digit that's dialed out.
I have users that want to access a general delivery mailbox (ext 210) from their phones. I have them monitoring the mailbox on their phones. To access the mailbox, you would dial the voicemail ext (280) or press the voicemail button, hit the * key, type in ext 210#, then the password of 1234#
They said that was too many steps so I wanted to set a speed dial that does something like 280,,*,,210#,,1234#. I tried it without the pauses but it did not work.
My idea might be totally off base but it was the only thing I could come up with.
Alright, yes, that won't be possible. Since they have a GDM, their primary extension could be setup as a member of the GDM. They could then login to their mailboxes and press option 9 to check for new messages in the GDM.
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