how do i call javascript inside CreateUserWizard1_CreateUserError

how do i call javascript inside CreateUserWizard1_CreateUserError


i gt followin script in my aspx page

<script language="javascript" type="text/javascript">
// <! Javascript to show the modalpopup

function ShowModalDialog()
{
 Page_ClientValidate();
 if(!Page_IsValid)
 $find('<%=AddUserVS_ModalPopupExtender.ClientID%>').show();
}


</script>


this i wanna  run on CreateUserWizard1_CreateUserError event...how??nyhelp??





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