4D version 6.5 contains a new command called SET HTTP REDIRECT. This command allows you to transform one URL into another one. The documentation tells you how to redirect to an html file. It also states that you can redirect to another web server, but it doesn't tell you how.
To redirect to another web server, you must use the format "//URL". If you don't, the address will be appended to the current URL.
SET HTTP REDIRECT("//www.4D.com")