Bug 63255 [Preferences] some pages cannot be displayed in high contrast
STEPS 1) Switch to High Contrast by selecting Window->Control Panl->Accessibility Resources 2) Start Eclipse 3) Open the preferences page 4) Select Colors and Fonts 5) Select a diffrent page 6) new page not displayed.
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
public void shellActivated(ShellEvent e) {
				if (lastShellSize == null)
					lastShellSize = getShell().getSize();
			}
		});
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.window.Window#constrainShellSize()
	 */
	protected void constrainShellSize() {
		super.constrainShellSize();
		
		if (lastShellSize == null)
			lastShellSize = getShell().getSize();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.dialogs.Dialog#createButtonsForButtonBar(org.eclipse.swt.widgets.Composite)
	 */
	protected void createButtonsForButtonBar(Composite parent) {
		
		okButton = createButton(parent, IDialogConstants.OK_ID,
				IDialogConstants.OK_LABEL, true);
		getShell().setDefaultButton(okButton);
		createButton(parent, IDialogConstants.CANCEL_ID,
				IDialogConstants.CANCEL_LABEL, false);
		if (isHelpAvailable) {