Use specific IP for outbound traffic.

Hello, I have 3 IPs in my VPS. Everytime I request to a site it uses only 1 IP as gateway. So all the outbound traffic goes thorough that IP. What I want is one of my script will always communicate using an specific ip. Not default one. I'll use 3 scripts for 3 IPs. How can I do that? I know it can be done by changing the routing table. I think this technique has a problem. If one script changes the gate way to its own IP other script will be using that IP too. Is there any way to achieve this without changing the routing table gloablly? -- Shiplu Innovation distinguishes bet ... ... (ask Steve Jobs the rest)