Site Actions Menu Items popping up behind the OpenStreetMaps layers in IE browser

Hi All,

         We have upgraded the Moss 2007 site to SharePoint 2010 with out visual upgrade .And after upgradation the site action menu is coming behind OpenStreetMaps layers instead of poping up in IE 9 browser .Below is the image we are getting in IE 9

         But the site is working perfectly in Google Chrome.Can any one help me how can I solve the issue

Samar