Ubuntu – Error while installing thesql-server-5.1

I need to install mysql-server-5.1 on ubuntu 11.10. While installing with apt-get I am getting

dpkg: error processing mysql-server-5.1 (--configure): subprocess installed post-installation script returned error exit status 1

I have tried following things:

sudo apt-get purge mysql-common

rebboting the machine and again trying to install mysql by running sudo apt-get
install mysql-server-5.1 but no success. Still I am getting the similar error.

In SYSLOG I am getting following lines:

Dec 11 20:26:02 ubuntu mysqld[11272]: 111211 20:26:02  InnoDB: Shutdown completed; log sequence number 0 145554
Dec 11 20:26:02 ubuntu mysqld[11272]: 111211 20:26:02 [Note] /usr/sbin/mysqld: Shutdown complete
Dec 11 20:26:02 ubuntu mysqld[11272]: 
Dec 11 20:26:02 ubuntu mysqld[11291]: 111211 20:26:02 [Note] Plugin 'FEDERATED' is disabled.
Dec 11 20:26:02 ubuntu mysqld[11291]: 111211 20:26:02  InnoDB: Initializing buffer pool, size = 8.0M
Dec 11 20:26:02 ubuntu mysqld[11291]: 111211 20:26:02  InnoDB: Completed initialization of buffer pool
Dec 11 20:26:02 ubuntu mysqld[11291]: 111211 20:26:02  InnoDB: Started; log sequence number 0 145554
Dec 11 20:26:02 ubuntu mysqld[11291]: 111211 20:26:02  InnoDB: Starting shutdown...
Dec 11 20:26:08 ubuntu mysqld[11291]: 111211 20:26:08  InnoDB: Shutdown completed; log sequence number 0 145554
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08 [Note] Plugin 'FEDERATED' is disabled.
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08  InnoDB: Initializing buffer pool, size = 8.0M
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08  InnoDB: Completed initialization of buffer pool
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08  InnoDB: Started; log sequence number 0 145554
Dec 11 20:26:08 ubuntu mysqld[11306]: ERROR: 1050  Table 'plugin' already exists
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08 [ERROR] Aborting
Dec 11 20:26:08 ubuntu mysqld[11306]: 
Dec 11 20:26:08 ubuntu mysqld[11306]: 111211 20:26:08  InnoDB: Starting shutdown...
Dec 11 20:26:13 ubuntu mysqld[11306]: 111211 20:26:13  InnoDB: Shutdown completed; log sequence number 0 145554
Dec 11 20:26:13 ubuntu mysqld[11306]: 111211 20:26:13 [Note] /usr/sbin/mysqld: Shutdown complete
Dec 11 20:26:13 ubuntu mysqld[11306]:

Let me know how to solve this issue.