X11 is installed, but a IE for mac is not finding it..

I am trying to install IE for mac from here:
http://www.kronenberg.org/darwine/

I made sure that X11 was installed per the instructions. I have OSX 10.4.11 so I triple checked to see that I had X11 and even recently re installed my OS and triple checked..

So when I go to open the DARWINE program, I get this error:

"11 is not installed, or not up to date. Install X11 from Your OS X installation DVD, then run "Software Update" from the Apple menu."

So even though i checked, I tried to download X11 from the apple website and I get this:
"you can not install X11 on this volume. Newer Software already exists."

I have even tried to delete it and reinstall, but the DARWINE program STILL can not find it!!

I just want it for website testing purposes