From scratch: Get the Virtuoso package provided by Francois. These are zipped information, plz refer to the official guide for better explenation.

Install the required packages:

sudo aptitude install autoconf automake libtool flex bison gperf gawk m4 make libssl-dev
tar xzvf virtuoso.tar.gz
cd virtuoso
./configure --prefix=/usr/local
make
sudo make install
cd /usr/local/var/lib/virtuoso/db/
sudo virtuoso-t -f & 

I'll add asap the config to expose your service if you are using virtuoso inside a virtual box machine.

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For the SemWeb? installation contest I was looking on the web for a simple way to install Virtuoso on my virtualized Ubuntu server 9.10

Note: Virtuoso v5.0.12

It seems that kubuntu guys are very excited about semantic web & desktop  http://www.kubuntu.org/news/kde-sc-4.4-rc-2 and their interest come from this application  http://nepomuk.semanticdesktop.org/xwiki/bin/view/Main1/.

just few lines:

sudo aptitude install python-software-properties
sudo add-apt-repository ppa:kubuntu-ppa/beta
sudo apt-get update
sudo aptitude install virtuoso-server
sudo aptitude install virtuoso-drivers