The iPAQ hx4700 has the Outlook client already built into it. How you connect the mobile clients is all dependant on your requirements. They could connect to a WAP (Wireless Access Point), use ActiveSync on a workstation, or potentially connect via a carrier to an ISP and access your server remotely.
You can start your research by looking at the Microsoft Exchange 2003 web page and these articles:
http://www.microsoft.com/technet/prodtechnol/exchange/2003/library/cliaccgde.mspx
SF
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