Why doesn't ice:commandButton accept onmouseover/onmouseout when it's disabled?

I'm working with ICEFaces components and I have the need of setting a tooltip on an ice:commandButton.

The button can be enabled or not according to particular conditions, but my problems is that when the button is disabled the tooltip is not displayed.

I display the tooltip by calling a Javascript method in the onmouseover attribute and close it via onmouseout.

Checking with IE dev tools, the two attributes do开发者_StackOverflow社区n't get rendered when the button is disabled.

How could I modify this behaviour?

Disabled components neither get focus nor react on any events.

HTML Reference:

When an element is disabled, it appears dimmed and does not respond to user input. Disabled elements do not respond to mouse events, nor will they respond to the contentEditable property.

As a workaround you can assign the tooltip to a <div/> around the commandButton.