Does anyone here have experience doing Flash design on a Mac? I've heard that freeware exists for this, but I'm having trouble finding it. Here are my constraints:

* I have OS X v10.3.9. The Flex 2 SDK available for free download at Adobe's site says I need v10.4.x or better.
* I don't currently have any money to buy OS X v10.4 or any other software. I am, however, willing to work with something bare bones, even if it's just a text editor to write Actionscript and a compiler to create SWF files.
* I've designed in other programming languages before (PHP, Java, etc), but not Flash. So, I'm not even familiar with the "professional" software, much less any "DIY" approaches that may exist.

I realize I may be asking for the impossible here, but any thoughts would be appreciated...