jQuery UIの buttonで角丸するには DD_roundies？

Achieving Rounded Corners in Internet Explorer for jQuery UI with DD_roundies | Filament Group, Inc., Boston, MA

jQuery UI is built upon a powerful CSS Framework, including round corners that utilize CSS3's border-radius property. Unfortunately, CSS3 border-radius is only supported by Safari and Firefox, leaving browsers such as Internet Explorer to gracefully degrade to square corners.

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