LinuxQuestions.org - port forwarding

Hello again,
I now have the following problem. First my configuration is: Ubuntu RC 6.06 server with:
eth0 the 'internet' connection
eth1 the lan with the ip 192.168.0.1
On my Windows computer i have the ip 192.168.0.10, the linux is setup to be a 'router' with

Code:

iptables -P FORWARD ACCEPT

iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

echo 1 > /proc/sys/net/ipv4/ip_forward

Due to the fact that i'm away most of the time i need to be able to connect to both my computers, on the linux machine i use ssh, and for the windown i what to use a popular program Remote Administrator (radmin) that uses port 4899 (this can be changed). So what i want to do is to be able to access on port 4899 the windows PC trough my linux. I tried port forwarding with some commands found on this forum:

Code:

iptables -t nat -A PREROUTING -p tcp -d 192.168.0.1 --dport 4899 -j DNAT --to 192.168.0.10:4899

that did now worked so i tried

Code:

iptables -t nat -A PREROUTING -p tcp -d 82.76.84.224 --dport 4899 -j DNAT --to 192.168.0.10:4899

So what am i doing wrong?
Thanks!