Bug 11317 Won't export some files to .jar.
Create a new java project called "Foo". In the file system, create a folder named "Foo scripts", and in this folder create a file named "foo.txt". Drag this folder into the eclipse packages view and add it to the "Foo" project. Now try to export the project "Foo" to a .jar file. Only the manifest file shows up, even if the file "foo.txt" is checked!
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarFileExportOperation.java
while (iter.hasNext())
			exportElement(iter.next(), progressMonitor);
	}
	/**
	 * Returns an iterator on a list with files that correspond to the
	 * passed file and that are on the classpath of its project.
	 *
	 * @param	file			the file for which to find the corresponding classpath resources
	 * @param	pathInJar		the path that the file has in the JAR (i.e. project and source folder segments removed)
	 * @param	javaProject		the javaProject that contains the file
	 * @return	the iterator over the corresponding classpath files for the given file
	 */
	protected Iterator filesOnClasspath(IFile file, IPath pathInJar, IJavaProject javaProject, IProgressMonitor progressMonitor) throws CoreException {
		IPath outputPath= javaProject.getOutputLocation();
		IContainer outputContainer;		
		if (javaProject.getProject().getFullPath().equals(outputPath))
			outputContainer= javaProject.getProject();
		else {
			outputContainer= createFolderHandle(outputPath);
			if (outputContainer == null || !outputContainer.isAccessible()) {
				String msg= JarPackagerMessages.getString("JarFileExportOperation.outputContainerNotAccessible"); 
				throw new CoreException(new Status(IStatus.ERROR, JavaPlugin.getPluginId(), JavaStatusConstants.INTERNAL_ERROR, msg, null));
			}
		}
		if (isJavaFile(file)) {
			
			boolean hasErrors= fJarPackage.hasCompileErrors(file);
			boolean hasWarnings= fJarPackage.hasCompileWarnings(file);
			boolean canBeExported= canBeExported(hasErrors, hasWarnings);
			if (!canBeExported)