Yup, its a matter of all the modules for php4 vs. php5 - just gotta install 'em all and remove the php4 ones.
dpkg -l | grep -i php4
Will show which php4 packages are still installed. Replace 'em with the php5 versions and remove the php4 versions.
Originally Posted by falko
It seems as if the command line PHP is version 4 still. Try this:
apt-get install php5-cli