iphone scrolling

When I first started using this excellent site a few months ago I accidentally discovered the cool autoscroll feature on my iphone.  You just tap once and it slowly scrolls one page length.  It was perfect!!  Unfortunately when I updated to the new iphone OS this feature is became all screwed up; you tap once and it zips back to the top of the page.  arrrggh!  very annoying!  Any ideas on how to fix that?  Not sure if it's the OS or a new version of Safari that's responsible....
Thanks again