         if (!thumb)
         {
             thumb = new Button();
+            thumb.minHeight = minThumbHeight; 
             thumb.setStyle("skinClass", thumbSkinClass);
             thumb.width = layoutMeasuredWidth;
             thumb.height = layoutMeasuredWidth;

import spark.components.Button;
import spark.components.VScrollBar;
import spark.skins.mobile.supportClasses.MobileSkin;


/**
 *  ActionScript-based skin for VScrollBar components in mobile applications. 

            case DPIClassification.DPI_320:
            {
                layoutMeasuredWidth = 12;
                paddingRight = VScrollBarThumbSkin.PADDING_RIGHT_320DPI;
                paddingVertical = VScrollBarThumbSkin.PADDING_VERTICAL_320DPI;
                break;
            }
            case DPIClassification.DPI_240:
            {
                layoutMeasuredWidth = 9;
                paddingRight = VScrollBarThumbSkin.PADDING_RIGHT_240DPI;
                paddingVertical = VScrollBarThumbSkin.PADDING_VERTICAL_240DPI;
                break;
            }
            default:
            {
                // default PPI160
                layoutMeasuredWidth = 6;
                paddingRight = VScrollBarThumbSkin.PADDING_RIGHT_DEFAULTDPI;
                paddingVertical = VScrollBarThumbSkin.PADDING_VERTICAL_DEFAULTDPI;
                break;
            }
        }

        // The minimum height is set such that, at it's smallest size, the thumb appears
        // as high as it is wide.
        minThumbHeight = (layoutMeasuredWidth - paddingRight) + (paddingVertical * 2);   
    }
    
    //--------------------------------------------------------------------------
