Cisco interVlan routing-L3 switch & DMZ

Hello! I need someone quick to assist with some changes being done to an existing network. The main skills involve Cisco routing & switching as well as some firewall skills. The firewall happens to be a Sonicwall NSA 2400, however if you understand firewall concepts well you may not need specific Sonicwall knowledge. We can apply any recommended changes. I need help setting up interVlan routing between two VLANS (one for voice, one for data), and configuring a DMZ and routes to allow a remote teleworker gateway server in the DMZ to get to one of the two VLANS, where the PBX resides. We have an existing LAN, utilizing several connected Cisco 2960 L2 switches and a 3560 L3 switch. They are trunked together running VTP in transparent mode with two VLAN's configured: VLAN1 and VLAN6. VLAN6 is dedicated to the PBX and VOIP handsets. VLAN1 is the main LAN for Pc's, internet gateway etc. A Mitel teleworker gateway server has been set up in the Sonicwall's DMZ. Outside teleworker phones can connect to the gateway server. However, this gateway server needs to communicate with the PBX and phones on VLAN6 (peer to peer extension calling). InterVlan routing is not yet set up; it is needed to allow the PBX to talk with the Exchange server for unified messaging, as well as (I think) to allow the gateway server to get back to the PBX & phones on VLAN6. I have a Visio diagram - see attached. One more curveball in the process: We are bringing up the Microsoft Essential Business Server 2008 (EBS), a 3 server suite. Even though we have a Sonicwall NSA 2400 at the perimeter, we have to install the EBS security server, which runs Threat Management Gatewat 2010 (a.k.a. the newest version of ISA 2006). EBS will not allow you to run with this server. But, we can set it to "low" security mode and it does very litte; traffic passes through it and to the correct EBS server for email, remote web workplace etc. What this means is that today the Sonicwall's internal interface is assigned VLAN1's gateway. But when we bring up EBS in a few days, TMG's internal interface will be the gateway. TMG's external interface is on a new subnet, with the Sonicwall's internal LAN interface as its gateway. Check out the drawing and it will make more sense. I am hoping to develop a relationship with someone who can do additional work in the future, including a review of the current Cisco IOS programming, network performance, and the addition of several branch offices that will be opened very soon.