Ubuntu 12.04 LTS

Fast installation

apt-get -y install php5-gd php5-mysql php5 php5-cli apache2 libapache2-mod-php5 tshark mtr mysql-server php5-mcrypt librsvg2-bin gsfonts
cd /usr/src/
wget --content-disposition http://www.voipmonitor.org/current-stable-sniffer-static-64bit.tar.gz
tar xzf voipmonitor*.tar.gz
cd voipmonitor*
./install-script.sh
mysqladmin create voipmonitor
# edit /etc/voipmonitor.conf and set appropriate mysql password
/etc/init.d/voipmonitor start
cd /var/www
wget "http://www.voipmonitor.org/download-gui?version=latest&major=5&phpver=53&festry" -O w.tar.gz
tar xzf w.tar.gz
mv voipmonitor-gui*/* ./
rm -f index.html
wget http://voipmonitor.org/ioncube/x86_64/ioncube_loader_lin_5.3.so -O /usr/lib/php5/20090626/ioncube_loader_lin_5.3.so
mkdir /var/spool/voipmonitor/
chown www-data /var/spool/voipmonitor/
wget http://sourceforge.net/projects/voipmonitor/files/wkhtml/0.10.0_rc2/wkhtmltoimage-x86_64 -O "/var/www/bin/wkhtmltoimage-x86_64"
chmod +x "/var/www/bin/wkhtmltoimage-x86_64"
wget http://sourceforge.net/projects/voipmonitor/files/wkhtml/0.10.0_rc2/wkhtmltopdf-x86_64 -O "/var/www/bin/wkhtmltopdf-x86_64"
chmod +x "/var/www/bin/wkhtmltopdf-x86_64"
wget http://voipmonitor.org/ioncube/x86_64/ioncube_loader_lin_5.3.so -O /usr/lib/php5/20090626/ioncube_loader_lin_5.3.so
echo "zend_extension = /usr/lib/php5/20090626/ioncube_loader_lin_5.3.so" > /etc/php5/apache2/conf.d/ioncube.ini
chown -R www-data /var/www
/etc/init.d/apache2 restart

Now go to http://yourserver/ and finish the installation (you need the key from [1]