Crash PLESK after upgrading

[uncoke]

Today I was using PLESK 9 on debian 4 and all was working nice. I was checking update and installing it by PLESK... e then... Plesk stoped to work!

Now some file is missiing and Plesk is not running so I have downloaded

parallels_installer_v3.6.0_build100407.15_os_Debian_4.0_x86_64 and try tu installing/update the missing file.

This is what I do:

root@vserv:~# ./parallels_installer_v3.6.0_build100407.15_os_Debian_4.0_x86_64

Then i confirm the standard [n]

6. (*) Parallels Plesk Panel 9.5.4 (currently installed)

It download the files... then the error:

Installing packages
Reading package lists...
Building dependency tree...
psa-migration-manager is already the newest version.
psa-migration-agents is already the newest version.
The following NEW packages will be installed:
ruby-rails
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
2 not fully installed or removed.
Need to get 0B/140kB of archives.
After unpacking 1409kB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
ruby-rails
Authentication warning overridden.
(Reading database ... 63806 files and directories currently installed.)
Unpacking ruby-rails (from .../ruby-rails_1.2.2-0.279666_all.deb) ...
dpkg: error processing /var/cache/apt/archives/ruby-rails_1.2.2-0.279666_all.deb (--unpack):
trying to overwrite `/usr/bin/rails', which is also in package rails
Errors were encountered while processing:
/var/cache/apt/archives/ruby-rails_1.2.2-0.279666_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
ERROR: An error occurred on attempt to install packages.
Attention! Your software might be inoperable.
Please, contact product technical support.

Hmmmmm!!!! Can you help me?