Bug 103927 [build path] External jar Dialog cannot set both Javadoc Location and Java Source Attachment in one iteration
Add an external jar to the project. From the context menu of the jar select properties. Select Javadoc location, browse to the desired location. Select Java Source Attachment. Browse to an external file. Press OK. From the context menu of the jar select properties again. Javadoc location is empty. (At this point it can be entered again without problems)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/LibrariesWorkbookPage.java
private ListDialogField fClassPathList;
	private IJavaProject fCurrJProject;
	
	private TreeListDialogField fLibrariesList;
	
	private Control fSWTControl;
	private final IWorkbenchPreferenceContainer fPageContainer;
	private final int IDX_ADDJAR= 0;
	private final int IDX_ADDEXT= 1;
	private final int IDX_ADDVAR= 2;
	private final int IDX_ADDLIB= 3;
	private final int IDX_ADDFOL= 4;
	
	private final int IDX_EDIT= 6;
	private final int IDX_REMOVE= 7;
	
		
	public LibrariesWorkbookPage(CheckedListDialogField classPathList, IWorkbenchPreferenceContainer pageContainer) {
		fClassPathList= classPathList;
		fPageContainer= pageContainer;
		fSWTControl= null;
		
		String[] buttonLabels= new String[] { 
			NewWizardMessages.LibrariesWorkbookPage_libraries_addjar_button,	
			NewWizardMessages.LibrariesWorkbookPage_libraries_addextjar_button, 
			NewWizardMessages.LibrariesWorkbookPage_libraries_addvariable_button, 
			NewWizardMessages.LibrariesWorkbookPage_libraries_addlibrary_button, 
			NewWizardMessages.LibrariesWorkbookPage_libraries_addclassfolder_button,