Firewall/NAT

My setup is this.
Dynamic IP address (89.189.98.12)
                          I
                          I
               monowall (WAN)
               monowall LAN ip: 192.168.1.1
                          I
                          I
               server lan ip: 192.168.2.1

Server is not connected to internet and is configured to comunicate only with clients which ip is in 192.168.x.x subnet.
So how can I configure NAT when I make request from 89.189.98.12 that it sends request to server but with monowall ip address so that server firewall accepts the connection?
Inbound NAT doesn't work because monowall transfers request to server but server rejects 89.189.98.12 because that ip address isn't in servers allowed ip range.

Thank you.

Sounds like what you're asking for is source NAT'ing, which isn't possible in m0n0wall.

Isn't something like that possible with monowall Proxy function?

I have no idea what you mean by "proxy function", but it's not possible at all, in any fashion, to NAT source addresses with m0n0wall.

i use a little trick for stuff like this. unsure if you can solve your problem this way but here's how i reverse nat on monowall:
make a rule from wan to lan that does what you want to
save the configuration
edit it in 'vi' or wordpad
find the rule
reverse LAN and WAN in the rule
save file
upload / restore config
and you have a reverse rule that's working perfectly probably not supported and from the interface it shows empty fields where LAN and WAN should be.. but hey it works