By running this test with IE, FF, Safari and Opera, you can easily see the culprit with IE.

This test case has two buttons "DivLevelUpdate" and "FormLevelUpdate". The DivLevelUpdate button adds a div to the page which has an external CSS link. Clicking on "DivLevelUpdate" button should render a new blue div. It does happen with all browsers but IE.

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- The following button will add a div element with link element (external css), the new div should be blue.

- The following button will replace the link element (external css), the div should become blue.