Router static IP on my debian server

Dear All,
I have got 4 computers as follow;
1. Server 2008 "active directory installed"
a. 2 computers with windows seven as client.
2. Unix Debian Lenny
3. Static Ip address
4. Router which is Linksys WRT54GC wireless router
Problem I faced
If I connect my connection to Linksys WRT54GC wireless router from there to switch and from switch to all mention computers for Debian I get IP address like 192.168.*.* which prevent me to use putty to connect my server Debian, could you please give me a solution that I get my static IP on my debian server instead of 192.168.*.*

Regards
KhashayaR