need to enlarge sndbuf in openvpn but it doesn't change

[muhamed.shehata]

I'm running openvpn 2.0.9 and has issue of drooped packet on the tun interface when I googled it I found guys talk about changing rcvbuf,sndbuf,txqueuelen options but
when I tried to increase sndbuf larger than default value 65536 in my openvpn server but doesn't change
I tried through
1.running options "openvpn --dev tun0 --sdnbuf 524288"
2.putiing it in the config file with "sndbuf 524288" and restart
but when I make debug "openvpn --dev tun0 --verb 11"
Tue Nov 27 11:17:21 2012 us=640608 Current Parameter Settings:
Tue Nov 27 11:17:21 2012 us=642086 sndbuf = 65536


Anyone can help