Ну, в принципе, два варианта, почти одинаковых.
<div style="width: 200px; height: 100px; background: #ff9; overflow: auto;">
<div style="float: left">
<div style="height: 25px; background: #f99;"></div>
<div style="height: 25px; background: #99f;">text_text_text_text_text_text_text_text_text_text_text_text_text_text_text_text</div>
</div>
</div>
<div style="width: 200px; height: 100px; background: #ff9; overflow: auto;">
<div style="display: inline-block">
<div style="height: 25px; background: #f99;"></div>
<div style="height: 25px; background: #99f;">text_text_text_text_text_text_text_text_text_text_text_text_text_text_text_text</div>
</div>
</div>
Для IE6 вместо [var]inline: block[var] ставим
zoom: 1