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
private JarPackage fJarPackage;
	private IFile[] fDescriptionFiles;
	private Shell fParentShell;
	private Map fJavaNameToClassFilesMap;
	private IContainer fClassFilesMapContainer;
	private MultiStatus fProblems;
	
	/**
	 * Creates an instance of this class.
	 *
	 * @param	jarPackage	the JAR package specification
	 * @param	parent	the parent for the dialog,
	 * 			or <code>null</code> if no dialog should be presented
	 */
	public JarFileExportOperation(JarPackage jarPackage, Shell parent) {
		this(parent);
		fJarPackage= jarPackage;
	}
	/**
	 * Creates an instance of this class.
	 *
	 * @param	descriptions	an array with JAR package descriptions
	 * @param	parent			the parent for the dialog,
	 * 			or <code>null</code> if no dialog should be presented
	 */
	public JarFileExportOperation(IFile[] descriptions, Shell parent) {
		this(parent);
		fDescriptionFiles= descriptions;
	}
	/**