How to transfer voicemail across 2 mitel 3300 controllers

[infosyst]

We have 2 mitel controllers 1 at 8.10 and one at 8.5.
Which work great other than if someone has a VM on either they aren't able to
transfer it to the other. Could someone please recommended a solution?

Currently we've been using voicemail to email but it's kind of a clunky work around.

[johnp]

Yiu need to set up the vm networking form if using embedded