Hi, we have a 3rd-party VMS attached behind a M1 Opt11C, the VMS emulates M2008 digital phones and works pretty good, MWI is available. And a few months ago, we interworking the Opt11C with a remote Opt11C using PRI SL1 ND2 MWI, it's also okay when lighting remote side Message Waiting Lamp. I used same settings interworking the Main Opt11C+VMS with BCM50 R2 last night, everythig's fine, but the MWI is not functional at BCM50 side. The call can be routed back to VMS, and VMS records message into DN's Mailbox. Any ideas? Thanks.