virt-manager: "nc: unix connect failed"

I came across an annoying behaviour while trying to connect to a remote KVM hypervisor from a FreeBSD GUI. virt-manager failed to connect to the server and showed the following error message:

libvirtError: End of file while reading data: nc: unix connect failed: No such file or directory: Input/output error

In short, virt-manager tries to access to /usr/local/var/run/libvirt/libvirt-sock because it is compiled with a /usr/local PREFIX on FreeBSD. Of course they didn’t plan anything on a plain text configuration file. I figured out this has to be configured in GConf, for example using gconf-editor, simply replace:

qemu+ssh://user@host/system

with:

qemu+ssh://user@host/system?socket=/var/run/libvirt/libvirt-sock

Other parameters for remote URIs can be found at this address.