Hi,
Currently with RichFaces 3.1.0 RC3, this is what the HTML looks like for the DIV that contains the controls of a modal panel (whatever is put in the "controls" facet of the rich:modalPanel):
<div class="dr-mpnl-pnl-text rich-mpnl-text rich-mpnl-controls" style="float: right; padding-top: 3px; padding-right: 3px;"> ... </div>