I figured it out.
My classpath didn't contain anything to let the compiler know that the current directory was the place to find Engine.java.
I had to add a "." to my classpath. So now it looks like this in c:\autoexec.bat
set CLASSPATH=d:\javahome\blahblahblah;.;
the . means add the current directory to the classpath.
Still it's wierd that javac *.java worked. Maybe cause they were loaded into the compiler in the same instance.
hmmmmm
