on use of window.showModalDialog no buttons of parent window work

Question

hi,

i have a asp.net application and have a requirement to implement a new functinality on a existing aspx page. Let us say i have pageA.aspx, i have to add a new button to this page which will invoke a modal window pageB.aspx.

I have added a new HTML input button ("show image"), and on the onClick event i call a javascript function. The code of the function is as below.

function InvokeItemPic() 
{  
    returnValue = window.showModalDialog('PageB.aspx?item= 600010-012&company=ASG', '', 'dialogWidth=100;dialogHeight=100');
}

Now when i click on the new button, pageb.aspx appears as a modal window with no problems. Now i close the pageb.aspx, and return to pagea.aspx. Now, the actual problem, no buttons on the pageA.aspx work. There are some 4 other buttons apart from "show image", all of them do not work. But these buttons work before i click on "show image". I do not know what am i doing wrong here.

I tried to use window.open instead, still i found the same problem

Please some on help me, i need some desperately!!!!!

Nikhil