The original xls-file is created with MS Office 2004 for Mac. Opening in LO 3.3 the content will not be displayed. In OO 3.2.1 it works.
Created attachment 42676 [details] example file original ms office file
Created attachment 42677 [details] screenshot
Created attachment 42678 [details] screenshot OO3.2.1
Can't reproduce in Mac OS X 10.6.6 LibreOffice 3.3, Dutch Languagepack. Content perfect visible.
the "arial" font is the problem. LO3.3 do not work with the font "Arial" version 2.90. With version 3.05 it works.
Relaxing the severity a bit since there is a work around, and we can't really reproduce it.
I'm afraid we won't be able to fix this one. We don't even know if this is our bug, and even if it is, it only affects a narrow set of users it's not really worth the trouble.