Ext.Shadow sets height to -1 in IE

[capdan]

Using 3.4.1.1 on IE8

Clicking a dropdown caused an invalid argument error, and the dropdown doesn't open

Inside: Ext.Shadow = function(config)
...
case ("sides")
....
a.h -= 1

I fixed this by changing the line above to :
a.h = Math.max(0, a.h - 1);