scrollableDataTable hides modal panel

[Shaiju scientia]

Hi,
I am using scrollable data table to get the row selection feature(Please let me know if anybody have a different suggestion for this). However the issue now is, I have a button in the same page and on clicking that, i have to show a modal panel(a confirmation dialog box). But the modal panel always goes behind the scrollable data table.I mean the data table hides the modal panel.
This is is happening only with rich: scrollableDataTable .rich:data table works fine(of course not with the row selection) .
Ohh yes, this is happening only with Mozilla Firefox. in IE8 and chrome its working fine. anybody have any suggestion?

Thanks in advance

Shaiju