function selectMenu(id)
{
   var objId = document.getElementById(id);
    if(id == 'homeTab'){ 
       objId.className = 'menuOver';   
    }else if(id == 'learnTab'){
       objId.className = 'menuOver';    
	}else if(id == 'collaborateTab'){
       objId.className = 'menuOver'; 
    }else if(id == 'subscribeTab'){
       objId.className = 'menuOver';    
	} 	
}