Redirecting traffic to another server.

[kurdak]

Hello.
I have only one external IP address.
Server A has internal IP 192.168.0.1, has released all the ports.
Server B is the internal ip 192.168.0.2.
On the server A and B is installed ISPCP.
I'd like to redirect traffic from server A to server B, when they enter one of my domains.
I would also like to have access to SSH, FTP, SMTP, POP3, IMAP on the server B.
How do I set the server and that all this work.

Sorry for my poor english, and thank you for your help.