autoproj update fails

Dear Sirs,

I have installed toolchain 2.3.1 and I am trying to update to current version.

I wen in my root directory and issued the command

autoproj update.

It ends with the following error:

manifest /usr/src/orocos/utilrb/manifest.xml of utilrb from orocos.toolchain lists 'ruby' as dependency, which is listed in the layout of autoproj/remotes/orocos.toolchain/orocos.autobuild but has no autobuild definition

What can I do ?

the complete output of the commands follows.

Thank you in advance,

Gianpaolo Rizzi.

root@giampy-P5KC:/usr/src/orocos# autoproj update
Access method to gitorious (git, http or ssh): git
autodetecting the operating system
Which prepackaged software (a.k.a. 'osdeps') should autoproj install automatically (all, ruby, os, none) ? all
looking for RubyGems updates
updating autoproj main configuration
autoproj: updating remote definitions of package sets
updating orocos.toolchain

autoproj: loading ...
run 'autoproj reconfigure' to change configuration options
and use 'autoproj switch-config' to change the remote source for
autoproj's main build configuration
the target operating system for Orocos/RTT (gnulinux or xenomai): xenomai
which CORBA implementation should the RTT use ? omniorb

autoproj: importing and loading selected packages
updating log4cpp
updating ocl
updating orogen
updating rtt
updating typelib
updating utilmm
updating utilrb

manifest /usr/src/orocos/utilrb/manifest.xml of utilrb from orocos.toolchain lists 'ruby' as dependency, which is listed in the layout of autoproj/remotes/orocos.toolchain/orocos.autobuild but has no autobuild definition