time picker in lightbox is on two lines - how best to fix?

When I create an event, the time picker in the lightbox looks like:

Time Period
  <time>  <date>  <month>  <year> --- <time>  <date>  <month>

See screenshot attached. Would it be best to tweak some value in the dhtmlxscheduler.css file, or is there some reason that the widgets are being displayed at an unexpected size or position?

I am running FF 8.0.1 on Mac OS X 10.6.8.

bolshe spaseebo - ray

This does not seem to occur on FF 9.0.1. It did happen on 8.0.1.

Are you using custom css on the same page?
Normally such situation must not occurs ( seems to be correct locally in FF 8 ), but can caused some global css styles

Is problem occurs in default samples or only in your app ?