Comment 4 for bug 734113

Second attempt to install mysql:

It would not install via Ubuntu Software Center (Installing Mythtv which mysql is a dependency). Attempted to install broken package via apt-get. Now I get the following error.

$ sudo apt-get install -f
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following extra packages will be installed:
  mysql-server-5.1
Suggested packages:
  tinyca
The following NEW packages will be installed:
  mysql-server-5.1
0 upgraded, 1 newly installed, 0 to remove and 12 not upgraded.
19 not fully installed or removed.
Need to get 0B/7,105kB of archives.
After this operation, 15.7MB of additional disk space will be used.
Do you want to continue [Y/n]? Y
Preconfiguring packages ...
(Reading database ... 632817 files and directories currently installed.)
Unpacking mysql-server-5.1 (from .../mysql-server-5.1_5.1.41-3ubuntu12.10_amd64.deb) ...
useradd: cannot lock /etc/shadow; try again later.
adduser: `/usr/sbin/useradd -d /var/lib/mysql -g mysql -s /bin/false -u 121 mysql' returned error code 1. Exiting.
dpkg: error processing /var/cache/apt/archives/mysql-server-5.1_5.1.41-3ubuntu12.10_amd64.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/mysql-server-5.1_5.1.41-3ubuntu12.10_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)