3. The method of claim 2 , wherein the step of retrieving the supplemental content from the content server comprises, via execution of the update handler on the user computer, converting the supplemental content included in the script file into an HTML format.
2. The method of claim 1 , wherein the content server operates in an Internet domain which is different from an Internet domain of said web site, and the step of retrieving the supplemental content comprises retrieving from the content server a script file that contains the supplemental content.