menu control in asp.net application and i.e browser

Hi

In my application i am using asp.net menu control, but i am facing small problem with this control, which is when i placing the mouse on the menu control i am not getting the sub menu popups at that i am written the following code on the master page

for that i am getting some other problem which is.


in my local system internet explorer version 7, when i am running my asp.net local application i am getting the menus but the same application hosted on the some hosting server and try to access the application from the same i.e 7 i am not getting the sub menus popup

in another system i am using i.e8, here the problem is reverse,

when i am running the application locally i am not getting the sub menus popup, but in the same system with the same i.e8 browser i am trying to access the application which is hosted in a hosting server i am  getting the sub menus popup

here i am writing the code which i used in master page to getting menus in i.e

which is in master page init method

protected void Page_Init(object sender, EventArgs e)
        {
         
            //The Following Code is required to make sure Menu is displayed properly in any browser.
            if (Request.ServerVariables["http_user_agent"].IndexOf("Safari", StringComparison.CurrentCultureIgnoreCase) != -1)
            {              
                Request.Browser.Adapters.Clear();
            }
      
     
        }


and i am also have one more issue with browser which is for the menu we applied style which is border for the main menu items but it is working on the internet explorer but it is not working in the Mozilla fire fox

for this is issue i am send a screen shot attaching to it post

if any body familiar with these issues please send the necessary solution for this. and if you have any links please forward me

Thanks& Regards
v.s.r.k.raju