I currently have CME 4.2 running at our headquarter location.  Because 4.2 does not support broadcast hunt groups, I have been using the overlay-dn method to have department extensions ring on multiple phones.  I am prepping for another office opening in another location in which I will be using CME 7.0 and a SIP trunk over a VPN.  I would like to avoid upgrading the headquarters router because it also is the gateway for an IPCC call center which was a bear to set up initially with CME.  Can anyone think of a way to have a department DN ring at both sites?  I know I could upgrade the headquarters CME to gain the use of broadcast hunt groups but again, I am looking to avoid that if possible.

Thanks in advanced.