IE7/IE8 are not handling my stress test of Raphael well, any ideas on how to improve performance?

I have created a basic stress test of Raphaёl (the well-known vector library) that displays 1000 objects (with connections) on screen.

In Firefox, this works splendidly. It displays all 1000 objects, and I can move them around at will with no visible lag (lag only ensues when I get to around 20,000 objects).

This is all on a mid-grade corporate desktop, keep in mind.

When I attempt to run my demo on IE7, it goes unbearably slow. And it doesn't run at all on IE8. It really only works reasonably well when I have around 50 objects on screen in IE7/IE8.

I am creating a 开发者_运维问答test suite that will at minimum require 200 test steps to be drawn at a time, and I really must figure out a way optimize my JavaScript code for IE7/IE8. Any ideas?