如何修改Vtiger 6.1.0所以我可以用上传图片类型创建自定义字段？

Question

How to modify Vtiger 6.1.0 so I can create custom field with upload image type on a module, for example Services..

What i Have done is: --> append this code in vtigercrm/modules/Services/views/Detail.php with strategy look at Products module code

class Services_Detail_View extends Products_Detail_View {

public function getHeaderScripts(Vtiger_Request $request) {
    parent::getHeaderScripts($request);
    $headerScriptInstances = parent::getHeaderScripts($request);
    $moduleName = $request->getModule();
    $modulePopUpFile = 'modules.'.$moduleName.'.resources.Edit';
    $moduleDetailFile = 'modules.'.$moduleName.'.resources.Detail';
    $moduleRelatedListFile = 'modules.'.$moduleName.'.resources.RelatedList';

    unset($headerScriptInstances[$modulePopUpFile]);
    unset($headerScriptInstances[$moduleDetailFile]);
    unset($headerScriptInstances[$moduleRelatedListFile]);

    $jsFileNames = array(
            'modules.Services.resources.Edit',
            'modules.Services.resources.Detail',
            'modules.Services.resources.RelatedList',
    );
    $jsFileNames[] = $modulePopUpFile;
    $jsFileNames[] = $moduleDetailFile;
    $jsFileNames[] = $moduleRelatedListFile;

    $jsScriptInstances = $this->checkAndConvertJsScripts($jsFileNames);
    $headerScriptInstances = array_merge($headerScriptInstances, $jsScriptInstances);
    return $headerScriptInstances;
}

}

What i am tring to accomplish is modifying the code of module Services to post image name to field i have created that is cf_xxx

I have tried comparing to Products & Contacts that have same function to upload image but I still could not find it.

Please help to make custom field i create in module Services worked..

and thanks...

:)