solito problema con apt-get

[ad <iummy@people.it>]

Preparing to replace libxt6 4.3.0.dfsg.1-6 (using
.../libxt6_4.3.0.dfsg.1-7_i386.deb) ...
Unpacking replacement libxt6 ...
dpkg: error processing
/var/cache/apt/archives/libxt6_4.3.0.dfsg.1-7_i386.deb (--unpack):
 trying to overwrite `/usr/X11R6/lib/X11/app-defaults', which is also in
package xnview
Errors were encountered while processing:
 /var/cache/apt/archives/libxt6_4.3.0.dfsg.1-7_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

che devo fare disinstallare il package xnview?

ciao