I'm planning on using Hibernate for persistence in an application I'm
writing, but am having some trouble initially building Hibernate.  I've
unzipped it into a directory, run the build batch file (I'm doing this
on Windows 2000), and I get the following errors:

"Unable to locate tools.jar. Expected to find it in C:\Program
Files\Java\jre1.5.0\lib\tools.jar"

(despite the fact that JAVA_HOME is set to "C:\Program
Files\Java\jdk1.5.0" which does contain tools.jar under lib)

"BUILD FAILED
C:\Documents and Settings\Administrator\My
Documents\code\third_party_packages\h
ibernate-3.0\build.xml:195: Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK"

(however, JAVA_HOME definitely points to the JDK).

I'm guessing this is an Ant issue, since the build script invokes Ant,
and that there's some issue with either my JAVA_HOME or CLASSPATH.
Also, my PATH does include the folder with the javac executable, though
it seems that the compiler's being invoked from the JVM and not the
command line.  What should I make sure is set as far as environment
variables go?  Is there anything I have to be change of in the batch
file or the Ant build script?

Any help would be much appreciated (I'm working on a neglected pet
project of mine that I'd like to start coding on again).