For iOS version 5+ I found this solution to simply replace iScroll: http://damien.antipa.at/2012/10/16/ios-pull-to-refresh-in-mobile-safari-with-native-scrolling/
The basic idea is to use:
<div class="scrollable">
Foo
</div>
.scrollable{
overflow-y:auto;
-webkit-overflow-scrolling:touch;
-webkit-transform:translateZ(0);
}
This does the trick. For older iOS versions (4 and lower) there is no solution for this problem (at least I couldn't find any).