simulate combox control

//-------------------------------------------------------------
//  @ Module: simulate select control, IE only.
//  @ Debug in: IE 6.0
//  @ Script by: blueDestiny, never-online
//  @ Updated: 2006-3-22
//  @ Version: 1.0 apha
//  @ Email: blueDestiny [at] 126.com
//  @ Website: http://www.never-online.net
//  @ Please Hold this item please.
//
//  API
//  @ simulateSelect(ctlSelIDs)
//    ctlSelIDs: select control IDs, split by ","
//
//  @ simulateSelect.style(ctlStyle[,selStyle][,unselStyle])
//    ctlStyle: main control combox css class name
//    selStyle: when mouseover or option focus css class name
//    unselStyle: options blur's css class name
//
//  @ simulateSelect.width=(widthPX)
//    widthPX must be a digit number.
//
//  @ simulateSelect.height=(heightPX)
//    heightPX must be a digit number.
//
//  -------------- for the next Version ----------
//  @ simulateSelect.readOnly = (blnReadOnly)
//    blnReadOnly must be a boolean type or a number type.
//  @ simulateSelect.addEvent(w, h)
//    w: fire handler's event.
//    h: handler function.
//-------------------------------------------------------------