Problems with Internet Explorer and compound class selectors

This paragraph has style "urgent" -- color blue

Lorem ipsum dolor sit amet, consectetuer adipiscing elit.Aenean varius nunc at ante. Morbi in mauris. Fusce massa. Lorem ipsum dolor sit amet, consectetuer adipiscing elit.Aenean varius nunc at ante. Morbi in mauris. Fusce massa.

This paragraph has style "warning" -- uppercase text

Praesent malesuada, lorem eget molestie sagittis, dui lectus tristique mi, at vulputate turpis est non mi.Duis fermentum enim eu lectus. Be sure to read the directions before you use any of these gasses. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos.

This paragraph has style "urgent and warning" -- blue and uppercase plus underlined

You need to read this disclaimer first: Sed molestie. Nullam pharetra urna non tellus. In non leo. In non orci. Pellentesque eget dui.