What you want is MTASC, which compiles Actionscript 2.  I think ming only supports AS1, and mxmlc only supports AS3.

You should be able to find or build an MTASC for Linux - I built one for the chumby itself (along with pretty much all of the  other Open Source Flash development tools), posted here.

Not yet - the chumby currently runs FlashLite 3.1, which is limited to Actionscript 2 and earlier.

Actionscript 3 runs on an entirely different virtual machine (AVM2).

We hope to be able to offer FlashLite 4.x, which would be able to run AS3 movies, soon.

"Soon".

Well, it's tricky because some of the timing is out of our hands (certification with Adobe, etc), as well as other unrelated changes we're making to the firmware.  The other issue is that since it's a rather substantial update, we need to do a full regression test of *everything* - the Control Panel (which is pretty complex when you test all the alarm combinations, etc), all the music sources, and every widget.

There have also been some substantial changes to the Flash security model in FlashLite 4 - we already know of some widgets that work in FL3 that don't work in FL4.

For instance, in FL4, it's possible to capture a JPEG, render it to a Bitmap, recompress it with AS3 and upload it somewhere.  Since that wasn't possible in FL3, loading JPEGs typically didn't require a crossdomain file, and they could be imaged to a Bitmap object.  Under FL4, however, you can still load the JPEG, but as soon as you try to make a Bitmap out of it, the security sandbox kicks in and prevents it.

Why is this a security issue, you ask?  Well, because a Flash movie could capture a JPEG from some server behind your firewall and send to a machine *outside* the firewall.

We may indeed take you up on that offer.