is ICMP blocked on your ISPs too?
if you're able to ping servers on the internet that means icmp packets are allowed and you can use icmp tunneling on pdproxy instead of tcp or udp if it's blocked.
actually tcp is slower than udp and icmp (at least here where i live which is not africa). i get full-speed on icmp here and the connection is stable all the time no matter what isp/tech i use (adsl/wireless/wimax/edge/3g).