maybe you could set-up a linux box (at your house, for example) to act as a NAT router and redirect traffic on one of the allowed ports to the server...
you could configure it with iptables so that all packets that arrive to it on port 80 (for example) get forwarded to port 2082 on the server...
Local PC ==> Firewall ==> NAT Box at Home ==> Internet Server
the main rules to do this on the NAT box would look something like this:
Code:
iptables -t nat -A PREROUTING -p TCP --dport 80 -s 100.100.100.100 \
-j DNAT --to-destination 200.200.200.200:2082
iptables -A FORWARD -p TCP --dport 2082 -d 200.200.200.200 -j ACCEPT
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
in this example, 100.100.100.100 is the IP of the corporate firewall and 200.200.200.200 is the IP of the cPanel server...
this way you wouldn't need to change anything on the server or the PC, you simply try to connect to port 80 on the NAT box and you'll actually be connecting to port 2082 on the server...
anyways, it's just a thought...