The PSDL Viewer won't pick up Java 3D, even though both it and Java are installed.

Here are my current specs:
OS: Windows 7 Home Premium 64-bit
CPU: AMD Athlon 64-bit dual core
ATI Graphics Video Card
4 GB RAM
500 GB Hard Drive
So far, I' ve tried the following:
Set Java.exe and/or Javaw.exe to run as Administrator - Didn't Work
Set Java.exe to Compatability Mode for Windows Vista (No Service Packs) - Didn't Work
How do I fix this? I keep getting a "Can't find Java3D" error, even though Java3d is installed. Why? I don't understand how it couldn't work even when Java is there.