I have iPhone 3G and recently I jailbreaked it. I got AT&T service just voice only. No data plane and I asked them to block all internet WAP access. I have WiFi at home and our company has Microsoft Exchange Server for push server. When I configure, it is not able to connect to server. Just wanted to confirm, can I access corporate Microsoft exchange server only via AT&T data service? I know my co-workers with same server configuration (without) any VPN, they can connect to this server. Any suggestions? Thanks.