I don't know if you even meant for us to be able to pass a custom class to 'iconCls'. But I did it and it worked great. I was able to use custom png icons for my tabpanel this way and made it look just fine for my needs.

I am trying to do the same thing for a tabPanel which I want docked at the bottom instead.

So if I take the exact same panel that works fine with my custom icons when tabBarDock: 'top', and I just change tabBarDock: 'bottom'.. the style of the tabs change and my custom class is completely ignored.

This happens on both ipad and in chrome desktop.

I realize it's possible to add our own custom icons using sass & compass but that method seems complicated and since the above method IS working when the tabPanel is docked at the top.. I figured it's probably a bug that it doesn't also work when the tabpanel is docked at the bottom.