How do I set up my blackbery to talk to my office if I have VPN?

Hey everyone,

I'm a bit confused here. I own a small business so I have Mac OS X Leopard server. I run an email server with imap on it, and i've set up vpn. From home, I can use PP2P or L2TP and vpn in no problem. I have a static ip set up there as well.

Right now, once I VPN in, I can go to mail, set up a new account, and then say my mail server is 10.0.0.25 which is my servers ip address. This is secure and works fine. Issue is, blackberry obviously can't connect that way.

Am I missing something, should I be opening ports for my static ip, and "not" requiring users to VPN in and use mail? Meaning anyone can get mail, and their mail server will be 74.x.x.x which is my static ip? I'm just confused since that seems less secure, but I don't see how the blackberry could connect then if the IP isn't available without VPN?