With MCM you should use GKAPI along with an external apps, which would do it. As far as I know there is only one apps called Click to Meet that supports Cisco's GKAPI where you can manipulate the digits. The GKAPI is available, so if you have programming skills, write a simple apps yourself.
Not so long ago in one of the previous posts a Cisco engineer was saying that there is a plan to put this feature in MCM cli.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.