inconsistency in results using Ctrl+F in libreoffice across 2 Debian boxes

[AG <computing.account@googlemail.com>]

Hey all

I have two machines, both running Debian stable (squeeze) and on both I 
jettisoned OpenOffice.org in favor of LibreOffice.

On one machine (box A) in Writer or in Calc I can use the keyboard 
commands Ctrl+F or Ctrl+Alt+F to "find" and "find and replace" 
respectively.  On Box B however, these keyboard commands don't work - 
instead the file drop down menu is activated.

Aside from the actual hardware inside the boxes, the installation was 
the same, the updates were the same, etc. so how do I begin debugging this?

Thanks for any assistance.

AG