      *  The class style used by this component. This can be a String, CSSStyleDeclaration
      *  or an IStyleClient. 
      *
-     *  <p>If this is a String, it is the name of a class declaration
-     *  in an <code>mx:Style</code> tag or CSS file. You do not include the period in 
-     *  the <code>styleName</code>. For example, if you have a class style named <code>".bigText"</code>,
+     *  <p>If this is a String, it is the name of one or more whitespace delimited class
+     *  declarations in an <code>mx:Style</code> tag or CSS file. You do not include the period
+     *  in the <code>styleName</code>. For example, if you have a class style named <code>".bigText"</code>,
      *  set the <code>styleName</code> property to <code>"bigText"</code> (no period).</p>
      *
      *  <p>If this is an IStyleClient (typically a UIComponent), all styles in the

            // set on Application.
            if (isPopUp)
            {
                if (FlexVersion.compatibilityVersion >= FlexVersion.VERSION_3_0 && _owner && _owner is IStyleClient)
                    inheritChain = IStyleClient(_owner).inheritingStyles;
                else
                    inheritChain = ApplicationGlobals.application.inheritingStyles;

    //  Note that initProtoChain is 99% copied into DataGridItemRenderer
    mx_internal function initProtoChain():void
    {
        var classSelectors:Array = [];

        if (styleName)
        {
            if (styleName is CSSStyleDeclaration)
            {
                // Get the style sheet referenced by the styleName property
                classSelectors.push(CSSStyleDeclaration(styleName));
            }
            else if (styleName is IFlexDisplayObject || styleName is IStyleClient)
            {
