Changing Selenium Jar to globally handle Modal Dialog box

• Unpack Selenium jar. (User JRE jar.exe utility)
  

• Open selenium-browserbot.js file.

• Search for function 'IEBrowserBot.prototype.modifyWindowToRecordPopUpDialogs'"

• Add following codes at the begning of this function

if(win.showModalDialog)
{
if (typeof(win.top.g_selRetVar) == 'undefined')
win.top.g_selRetVar = null;
win.top._UTL_SetSelRetVar = function (val){
win.top.g_selRetVar = val;
win.top.status = win.top.g_selRetVar + ' is returned from child';
};
win.showModalDialog = function( sURL, vArguments, sFeatures)
{
if ((typeof(win.top.g_selRetVar) != 'undefined') && (win.top.g_selRetVar!=null))
{
var temp = win.top.g_selRetVar;
win.top.g_selRetVar = null;
return temp;
}
try {
win.top.open (sURL, 'modal', sFeatures);
} catch(e){ win.showModalDialog(sURL, vArguments, sFeatures); }
};
}
if(win.close)
{
win.attachEvent('onbeforeunload', function _selhandler()
{
if(win.opener && win.opener._UTL_SetSelRetVar)
win.opener._UTL_SetSelRetVar(win.returnValue);
});
}

• Pack the jar again. (User JRE jar.exe utility)

If you do not wish to change your jar file you can inject the javascript through your script. This has been mentioned in
Handling Modal windows
Download modified Selenium RC