Bug 214212 Problem occurs when set the masterpage margin with ems/exs/pixcel units.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/metadata/DimensionPropertyType.java
}
	/**
	 * Validates the string value in the locale-dependent way. Possible valid
	 * property value is one of the following:
	 * <ul>
	 * <li>Null or blank string.</li>
	 * <li>A string with optional units. The string is of the form n( *)[u]
	 * where n is a decimal number with the decimal separator specified by the
	 * current locale, ( *) is optional white space, and [u] is an optional
	 * units specifier. Units can be any of the recognized BIRT units: in, cm,
	 * mm, pt, pc, px, em, ex or % . If the unit specifier is omitted, use the
	 * default for the design.</li>
	 * </ul>
	 * 
	 * @return object is of type <code>DimensionValue</code> or null.
	 * 
	 */
	public Object validateInputString( Module module, PropertyDefn defn,
			String value ) throws PropertyValueException
	{
		DimensionValue dim = DimensionValue.parseInput( value );
		if ( dim == null )
		{
			logger.log( Level.FINE,
					"The input string may be a blank string or without measure." 
							+ value );
			return null;
		}
		validateUnits( module, defn, dim );
		if ( !DimensionValue.DEFAULT_UNIT.equalsIgnoreCase( dim.getUnits( ) ) )