[z@zygon ~]$ sudo pacman -Syu virtualbox
:: Synchronizing package databases...
 core is up to date
 extra is up to date
 community is up to date
error: 'virtualbox': could not find or read package
[z@zygon ~]$ sudo pacman -Ss virtualbox
community/libvirt 0.8.1-1
    API for controlling virtualization engines (openvz,kvm,qemu,virtualbox,xen,etc)
community/virtualbox-additions 3.2.6-1
    Guest additions for VirtualBox