AS3: Saving a sprite to a file and reading it back?

Question

I'm using Actionscript 3 and I need to be able to write a vector graphic sprite to a file and then load it back later. Normally I'd just serialize it in a ByteArray, but apparently you can't serialize a sprite. But it's just data, so there's got to be some way of representing it in a file. I've Googled until my fingers are sore, but I can't seem to turn up anything. Does anyone know how this can be done? Thanks!