I am looking for Conference Bridge Hardware which will be compatible to both a Televantage system and the Nortel System. Both systems are acting as one large system. The voicemail is being utilized on the Televantage and calls are forwarded to a DID'S on the Mics/PRI. Let me know if you need more info. thanks

Check these folks out:

https://www.forum-com.com/confer_3.htm

Thank you I will check this out

Also, most LD and Local carriers offer this as a service (pay-per-minute/per-bridged call). Depending on usage, might want to way the cost of this instead of vesting in the cost of hardware.