IE browser hangs when reopens a pop up window from the sidebar

Question

Hi, I have a sidebar application, and the sidebar itself acts as a parent window. A child pop up IM window will open from this parent window by clicking a link. The problem is that, when we try to close the pop up IM window and reopen a pop up IM window, there is large time delay for opening the pop up IM window again ( IN ie6 the page can not be loaded). This issues is seen only in IE browser. IT works in Firefox perfectly. Actually Why this happened only for IE browser? Is it due to any permission problem?

The code is here,

a class="IM" href="#" title="IM" onclick='openWindow("http://localhost/myproject/web/run.php","mywindow", "width=250,height=250,status=1")'>IM

function openWindow(url,name,status)

{

try

{

    var WindowsNames = url.split('=');
            //Creating the contact object
    contact = rosterObj.roster[WindowsNames[1].toLowerCase()]['contact'];
            // Check whether the window connection object 'contact.chatW' exists and if there is already chat window opened 'contact.chatW.closed'
    if(contact.chatW && !contact.chatW.closed)
    {
        //Cheking for appending the chat message
        if(contact.chatW.name == name)
        {

        }
        //if the window is not opened, open the IM pop up window
        else
        {
            contact.chatW = window.open(url,name,status);
        }
    }
    //IF both the connection object and IM window is opened, will open a new pop up window
    else
    {
        contact.chatW = window.open(url,name,status);
    }
}
catch(e)
{
}

}

Thank you, Raju