dropdown button gets split into two lines

Created by: cberzan

See this example: http://jsfiddle.net/cberzan/hgCyD/3/. The dropdown on the right is in a table cell with white-space: nowrap;. This works as intended in Chrome (Linux / 18.0.1025.151). However, in Firefox (Linux / 11.0) and Opera (Linux / 11.64), the dropdown gets split into two lines:

Is there any way to prevent the dropdown from being split into two lines, short of specifying a fixed width?