How do I get my MultiVOIP to work through a firewall or proxy server?

The H.323 protocol uses dynamic ports. Current Multi-Tech proxy or firewall products do support H.323 dynamic ports when connecting the voip to the DMZ port. The H323 ports used by the MultiVOIP is as follows :
H.225 listen port = 1720 (TCP).
H.225 client port = Dynamic (16000 - 20000) (TCP).
H.245 listen port = Dynamic (16000 - 20000) (TCP).
H.245 listen port = Dynamic (16000 - 20000) (TCP).
RAS client port = Dynamic (16000 - 20000) (UDP).
RTP port (channel 1) = 5004 (UDP).
RTCP port (channel 1) = 5005 (UDP).
RTP port (channel 2) = 5014 (UDP).
RTCP port (channel 2) = 5015 (UDP).
RTP port (channel 3) = 5024 (UDP).
RTCP port (channel 3) = 5025 (UDP).
RTP port (channel 4 = 5034 (UDP).
RTCP port (channel 4)= 5035 (UDP).
RTP port (channel 5) = 5044 (UDP).
RTCP port (channel 5) = 5045 (UDP).
RTP port (channel 6) = 5054 (UDP).
RTCP port (channel 6) = 5055 (UDP).
RTP port (channel 7) = 5064 (UDP).
RTCP port (channel 7) = 5065 (UDP).
RTP port (channel 8) = 5074 (UDP).
RTCP port (channel 8)= 5075 (UDP).
Proprietary port for master/slave protocol = 5000 (UDP).

Note: This is not a H323 standard). The Proprietary Protocol uses special UDP ports to pass information, and these ports will need to be added to your firewall or proxy server.

Example protocol and ports required for the MultiVOIP are listed below.
Q.931 signaling, RTP and RTCP are used for call handling.
Ports used: Q.931: Q.931 signaling port Channel 1 = 900 Channel 2 = 902 Channel 3 = 904 Etc. RTP: Channel 1 = 5004 Channel 2 = 5006 Channel 3 = 5008 Etc. RTCP: Channel 1 = 5005 Channel 2 = 5007 Channel 3 = 5009 Etc.