Open Source Actionscript 3 or Javascript date utility classes?

I was wondering if anyone could point to an Open Source date utility class that is fairly robust. I find myself rolling my own when I want to do a lot of things I take for granted in C# and Java. For instance I did find a decent example of a DateDiff() function that I tore apart and another DatePart() function. Another examples would be parsing different date/time formats. I'm trying to avoid reinventing something if it's already built.

Another possibility may be a nice set of Javascript files that I can convert to ActionScript 3. So far I've found DateJS but I want to get a good idea of what is out there.

From stackoverflow Ian S

• as3corelib has the DateUtil class and it should be pretty reliable since it's written by some Adobe employees. I haven't encountered any problems with it.

  From hasseg

• There is also DP_DateExtensions, though I believe DateJS is more robust.

  From pkaeding

• Thanks for the answers, these libraries will help tremendously.

  From Ian S