@Zwagerman Unfortunately I don't agree as this should be from the client side, in fact I don't see any relation with server side as the client is sending the input and have all the controls of it.
So far it been very unclear why it can't be achieve and if it was a protocol or standard issue, but at least using another field to enter post number to automatically dial for all those conference number or extension will be perfect.
We are automating everything and all phone are doing it, it like a basic standard. Honestly this really make no sense to me as all my contacts and me deal everyday by dialing conference bridge or extension.