root@xgate:~# apt-get install percona-server-client-5.5 percona-server-common-5.5 percona-server-server-5.5
Reading package lists... Done
Building dependency tree
Reading state information... Done
Suggested packages:
  tinyca
The following NEW packages will be installed:
  percona-server-client-5.5 percona-server-common-5.5 percona-server-server-5.5
0 upgraded, 3 newly installed, 0 to remove and 3 not upgraded.
Need to get 0 B/57.2 MB of archives.
After this operation, 183 MB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
  percona-server-common-5.5 percona-server-client-5.5 percona-server-server-5.5
Install these packages without verification [y/N]? Y
Preconfiguring packages ...
Selecting previously deselected package percona-server-common-5.5.
(Reading database ... 106181 files and directories currently installed.)
Unpacking percona-server-common-5.5 (from .../percona-server-common-5.5_5.5.13-rel20.4-136.lucid_all.deb) ...
Unpacking percona-server-client-5.5 (from .../percona-server-client-5.5_5.5.13-rel20.4-136.lucid_amd64.deb) ...
dpkg: error processing /var/cache/apt/archives/percona-server-client-5.5_5.5.13-rel20.4-136.lucid_amd64.deb (--unpack):
 trying to overwrite '/usr/share/man/man1/mysqlcheck.1.gz', which is also in package mysql-client-core-5.1 5.1.54-1ubuntu4
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Unpacking percona-server-server-5.5 (from .../percona-server-server-5.5_5.5.13-rel20.4-136.lucid_amd64.deb) ...
dpkg: error processing /var/cache/apt/archives/percona-server-server-5.5_5.5.13-rel20.4-136.lucid_amd64.deb (--unpack):
 trying to overwrite '/usr/sbin/mysqld', which is also in package mysql-server-core-5.1 5.1.54-1ubuntu4
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Processing triggers for man-db ...
Processing triggers for ureadahead ...
Errors were encountered while processing:
 /var/cache/apt/archives/percona-server-client-5.5_5.5.13-rel20.4-136.lucid_amd64.deb
 /var/cache/apt/archives/percona-server-server-5.5_5.5.13-rel20.4-136.lucid_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
root@xgate:~#