unable to upgrade mysql using custombuild

A MySQL server package (MySQL-server-4.1.11-0) is installed.

Upgrading directly from MySQL 4.1 to MySQL 5.1 may not
be safe in all cases.  A manual dump and restore using mysqldump is
recommended.  It is important to review the MySQL manual's Upgrading
section for version-specific incompatibilities.

A manual upgrade is required.

- Ensure that you have a complete, working backup of your data and my.cnf
  files
- Shut down the MySQL server cleanly
- Remove the existing MySQL packages.  Usually this command will
  list the packages you should remove:
  rpm -qa | grep -i '^mysql-'

  You may choose to use 'rpm --nodeps -ev <package-name>' to remove
  the package which contains the mysqlclient shared library.  The
  library will be reinstalled by the MySQL-shared-compat package.
- Install the new MySQL packages supplied by Sun Microsystems, Inc.
- Ensure that the MySQL server is started
- Run the 'mysql_upgrade' program

This is a brief description of the upgrade process.  Important details
can be found in the MySQL manual, in the Upgrading section.
******************************************************************
error: %pre(MySQL-server-5.1.37-0.glibc23.i386) scriptlet failed, exit status 1
error:   install: %pre scriptlet failed (2), skipping MySQL-server-5.1.37-0.glibc23
Starting MySQL                                             [  OK  ]
Giving mysqld a few seconds to start up...
This script updates all the mysql privilege tables to be usable by
MySQL 4.0 and above.

This is needed if you want to use the new GRANT functions,
CREATE AGGREGATE FUNCTION, or the more secure passwords in 4.1

done

 Dumping database mysql
mysqldump: Error: 'Table 'INFORMATION_SCHEMA.FILES' doesn't exist' when trying to dump tablespaces

rpm -e MySQL-server-4.1.11-0 --nodeps

./build mysql