Oh, from viewing the link I can see that you want to install the standard linux edition for kOffice... I'm afraid it doesn't work like this..

You need a special version that has been compiled especially for the Meamo (5) platform and the Armel processor (in oppose to i386).

You can install this version using the easy-debian (which is an image of a real debian distribution), but it will probably work very (very) slow.

more details about easy-debian here:
http://talk.maemo.org/showthread.php...ht=easy+debian

I myself has never tried to install any deb file using easy debian so I can't help with that...

A dedicated version for n900 is coming (soon?), you can catch up following chande blog, the link is inside his thread:
http://talk.maemo.org/showpost.php?p=467353&postcount=5