Code:
var pnl=new Ext.Panel({html:'Some content'});
pnl.showBy(Ext.getBody());
The above code generates an exception. showBy only accepts an Ext.Component, passing Ext.Element throws an error: "Cannot read property "dom" of undefined".

And I believe the problem lies in this line of Ext.Component.alignTo:

Code:
varg = h.element,
I believe Ext.Components have a element property, but Ext.Element don't have it.