[CentOS] mysql won't start

OK so at some point I borked my mysql 4.1.20 installation on my
x86_64 system.  Possibly relevant: I have enabled the centosplus
repository in yum.conf because I needed a package from there.  I have
not upgraded mysql from there.

Everything was working, then "something" aparrently happened, and now
mysql won't start.  The logs say:

061031 11:37:38  mysqld started
061031 11:37:38 [ERROR] Can't start server : Bind on unix socket: Permission denied
061031 11:37:38 [ERROR] Do you already have another mysqld server running on socket: /var/lib/mysql/mysql.sock ?
061031 11:37:38 [ERROR] Aborting

061031 11:37:38 [Note] /usr/libexec/mysqld: Shutdown complete

Now the naive would presume that there is a permissions problem on
/var/lib/mysql/mysql.sock, right?  Certainly the web suggests that
this is the problem.

[root at urquell2 ~]# ls -ld /var/lib/mysql/mysql.sock /var/lib/mysql
ls: /var/lib/mysql/mysql.sock: No such file or directory
drwxrwxr-x  4 mysql mysql 4096 Oct 31 11:39 /var/lib/mysql

Or maybe I'm trying to run mysql as the wrong user?

[root at urquell2 ~]# cat /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Default to using old password format for compatibility with mysql 3.x
# clients (those using the mysqlclient10 compatibility package).
old_passwords=1

[mysql.server]
user=mysql
basedir=/var/lib

[mysqld_safe]
err-log=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

...so clearly mysql is trying to tell me something but can't use the right
words to describe the problem.

In the highly unlikely event that someone knows what mysql is trying to
say, can they tell me how I might fix this problem?

But more likely I would like to reinstall the RPMs since something is
broke, right?  Well that isn't so simple either.

[root at urquell2 ~]# rpm -e mysql
error: "mysql" specifies multiple packages
[root at urquell2 ~]# rpm -qa | grep mysql-4
mysql-4.1.20-1.RHEL4.1
mysql-4.1.20-1.RHEL4.1
[root at urquell2 ~]# rpm -e mysql-4.1.20-1.RHEL4.1
error: "mysql-4.1.20-1.RHEL4.1" specifies multiple packages

We are not even getting to the dependancy hell this will involve.

So how do I fix this problem?  I'd rather not pave the system and
start from scratch, but honestly if I'd done that the moment that
this problem manifested, I'd probably be up and running again by now.

-- 
 /\oo/\
/ /()\ \ David Mackintosh | Public Key: 
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