🚀 go-pugleaf

Hi everyone. 
I am trying to build someone else's application to work on Mac OSX,
but I can't seem to get the source code to compile in JBuilder 6. The
package I got from this other person has compiled class files and
source code. I've tried running it from the class files, but keep
getting a java error saying it can't find the classdeffile or
something. Anyway, I decided to try and import the source code to
JBuilder and let JB sort out the fiddly Java crap.
Anyway, here's what I did:

1) Created a new project 
2) The source files came in two separate directories, so I created two
folders in my project (called the same as the folders on disk) and
imported the sources into these folders.
3) I set the Application's main class to the file with the main method
in it
4) I try to compile the source

Obviously, it doesn't work and I hundreds of errors all in the form:

"BCKBrain.java": Error #:300 : class BCKRecord not found in class
BCK.ANN.BCKFiler at line 80, column 9

However, when I browse classes, there it is sure enough 'BCKFilter'
just where it should be. After a little more investigation, I found
that JB had compiled SOME of the source code files, but not all of
them .
Does it have something to do with the file structure? Does the file
structure dictate the package name in any way. E.g. do I have to have
a class that is in the package 'BCK.ANN' in the folder 'BCK/ANN/'?

Any help on this one would be very greatly appreciated. Thanks!