apt-file: error in creating child process for this terminal

[Fabio Marconi]

Binary package hint: apt

I have installed from Synaptic apt-file in a Lucid 64 bit updated.
Finished the installation appear a windows that ask for the update or creation of apt-file cache.
I click on execute now button, and appear a terminal empty, just the cursor, and a popup that said:
Error in creating the child process for this terminal.
---
Architecture: amd64
CheckboxSubmission: 24bfda22985f9f37974801ac35af0af3
CheckboxSystem: 4ed15c40009aa6f7770f606350a390a2
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
Package: apt-file 2.3.3
PackageArchitecture: all
ProcEnviron:
 LANG=it_IT.utf8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.32-24.39-generic 2.6.32.15+drm33.5
Tags: lucid
Uname: Linux 2.6.32-24-generic x86_64
UserGroups: adm admin cdrom dialout disk libvirtd lpadmin plugdev sambashare

[Fabio Marconi (fabiomarconi)]

apport information

[Fabio Marconi (fabiomarconi)]

in /var/log/apt/term.log i can see:
The system-wide cache is empty. You may want to run 'apt-file update'

as root to update the cache. You can also run 'apt-file update' as

normal user to use a cache in the user's home directory.
Then running in a terminal:
sudo apt-file update
the cache is updated succesfully.