In iSeries2web v. 5.3 a feature to create tabs is implemented
(The examples here under is not in text, as the wiki will try to interpet the tab tags. same thing goes for the Sctipt tag in the javascript example)
It's easy to use and is made only in HTML.
Just use this simple notification:

Here is a real example of code (On tab 2 it uses the new Ajax function, just to show that scripting easily can be used inside the tabs) :

And the result: