If there is a problem with dist-upgrade like this:
Errors were encountered while processing:
/var/cache/apt/archives/libuniconf4.6_4.6-1_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Solution:
dpkg --purge libuniconf4.4 wvdial && apt-get -f install

(re-install wvdial if you need it)