Bug 56637 [Preferences] DialogMessageArea image is too large
Is the background color of the error shown by DialogMessageArea to be changed? Or do you intend to leave it as it is right now? The error message looks a little out of place in the current implementation (being surrounded by white space).
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) {
			createButton(parent, IDialogConstants.HELP_ID, IDialogConstants.HELP_LABEL, false);
		}
	}
	/* (non-Javadoc)
	 * @see org.eclipse.jface.window.Window#createContents(org.eclipse.swt.widgets.Composite)
	 */