Bug 11437 jar packager: no error message but buttons disabled
20020314 on the 'jar manifest' wizard page, if you select to use existing manifest file there's no error message but next and finish are disabled user should be informed what to do to make the wizard happy
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/jarpackager/JarManifestWizardPage.java
pathStr= ""; 
			fJarPackage.setManifestLocation(new Path(pathStr));
			
			fJarPackage.setSealJar(settings.getBoolean(STORE_SEAL_JAR));
		}
	}
	/**
	 *	Stores the widget values in the JAR package.
	 */
	protected void updateModel() {
		if (getControl() == null)
			return;
		
		
		fJarPackage.setGenerateManifest(fGenerateManifestRadioButton.getSelection());
		fJarPackage.setSaveManifest(fSaveManifestCheckbox.getSelection());
		fJarPackage.setReuseManifest(fReuseManifestCheckbox.getSelection());
		String path;
		if (fJarPackage.isManifestGenerated())
			path= fNewManifestFileText.getText();
		else
			path= fManifestFileText.getText();
		if (path == null)
			path= ""; 
		fJarPackage.setManifestLocation(new Path(path));
		
		fJarPackage.setSealJar(fSealJarRadioButton.getSelection());
	}
	/**
	 * Determine if the page is complete and update the page appropriately.