I'd be interested in seeing which catalogues you have enabled:

$ cat /etc/apt/sources.list.d/hildon-application-manager.list

also, you should run the following:

$ apt-cache policy xarchiver

With this we might learn the reason why apt-get is installing the wrong version.

If you're in a hurry and just want to get over this, go to http://maemo.org/packages/package_in...6-7fremantle7/ and download the .deb, then install it using dpkg:

(as root) # dpkg -i /path/to/xarchiver_0.4.6-7fremantle7_armel.deb