Looks like a good validating Flash-embedding solution for your XHTML pages.

bobbyvandersluis.com | Unobtrusive Flash Objects (UFO) v1.0

Unobtrusive Flash Objects (UFO) v1.0

UFO is a DOM script that detects and embeds Flash objects. It contains several features and best practice techniques that other scripts currently don’t have. UFO is inspired by Geoff Stearns’ FlashObject.

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