1000 pts E-mail work and e-mail

We are using a LAN based e-mail server at work. (wingate/mdaemon) We have set it up as a proxy server.
Several employees use laptops. When they take them home they wish to access their private home e-mail as well as www. This can be done but they have to go into internet options and turn off the proxy settings, change their default e-mail from work to home etc. etc.
It is a pain for the user. We are currently using Win 98 and IE4 and IE5. Any easy solutions? 1000 pts if I receive a good workable solution. Thanks, JOhn