Layout error in "schedule publication" error dialog

When scheduling a publication in the past, an error dialog pops up. The layout of this dialog is broken in Firefox 3.6.6 and IE7 (it shows scroll bars; see the screenshots for details).

Steps to reproduce:
1. create a new document
2. schedule the document for publication
3. choose a time in the past and click "OK"

Expected behavior: the error dialog looks good
Actual behavior: the error dialog does not look good