TLS Handshake failed

[abdjbr]

i have setup Openvpn on CentOS Linux , followed the general steps and change the default port from 1194 to 2050 ,
i have tested several internet links , from my country's ISP the connection is failing in the TLS handshake step , yet the port is opened ( telnet x.x.x.x 2050 is working and i see log in the server sides confirm the connection is initiated )
am getting this :
TLS: Initial packet from x.x.x.x:2832, sid=0464d4fc c165e3a9
>LOG:1353749252,N,x.x.x.x:2831 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
>LOG:1353749252,N,x.x.x.x:2831 TLS Error: TLS handshake failed
>LOG:1353749252,N,x.x.x.x:2831 Fatal TLS error (check_tls_errors_co), restarting

and on the client side :
Sat Nov 24 09:31:26 2012 Attempting to establish TCP connection with x.x.x.x:2050
Sat Nov 24 09:31:26 2012 TCP connection established with x.x.x.x:2050
Sat Nov 24 09:31:26 2012 TCPv4_CLIENT link local: [undef]
Sat Nov 24 09:31:26 2012 TCPv4_CLIENT link remote: x.x.x.x:2050
Sat Nov 24 09:31:26 2012 TLS: Initial packet fromx.x.x.x:2050,sid=86f85717d4918cff
Sat Nov 24 09:33:31 2012 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Sat Nov 24 09:33:31 2012 TLS Error: TLS handshake failed
Sat Nov 24 09:33:31 2012 Fatal TLS error (check_tls_errors_co), restarting
Sat Nov 24 09:33:31 2012 TCP/UDP: Closing socket
Sat Nov 24 09:33:31 2012 SIGUSR1[soft,tls-error] received, process restarting
Sat Nov 24 09:33:31 2012 Restart pause, 5 second(s)

i have the same firewall configuration for all links ,

the openvpn service is setup on the a VPS Machine , the connection is working from one link only .

please assist .