Well I have absolutely no idea what is you want, because your post bears no resemblance to your Topic Title.
avast does support win98 even win95 and there are many forum members that use still win98 and avast works just fine. I am totally confused about reference to oldversion.com, there should be no reason to use an old version of avast
So if you would like to explain exactly what the problem is we can try and help you.
You ask a question yet don't give any information about what it is that avast should support.
Thank you avast for putting something in that really is not that difficult.
Why not support it if you already made the software cabable to support it?
The fact that avast can do something which isn't supported by the old OS isn't the fault of avast when even Microsoft won't support win9x
Please modify your post and remove any language unsuitable for minors (there are many of those also on the forums) thanks.