Getting the parent of the base page that opens a ModelDialog

Hi;

I have this ModalDialog window. The opener page is inside an iframe. What i want to do is i want to reach the parent of the opener page of the dialog. You can reach the opener with window.dialogArguments. But you cannot use parent.window.dialogArguments.
To make things clear here is an example code. If i was using window.open instead of showModalDialog than my code would look like this.

function someFunction()
{
    valueIWantToGet = opener.parent.document.all.tags( "INPUT" )( "someField" ).value;
}

but since i am using a Modal Dialog the code has to be like this.

function someFunction()
{
    windowOpener = window.dialogArguments;
   //Here in the line above we get the opener window.No prob. so far.
 
    valueIWantToGet = windowOpener.parent.document.all.tags( "INPUT" )( "someField" ).value;
    //But when we try to get the parent of the opener window then the problems start
}


So if anybody knows the solution please share it with me. :) Thanks...