Socket problems

Greetings

I am trying to install DBD::mysql on a quad dual-core Xeon system running 
RedHat Enterprise v4. I just installed mysql 5.0.21 from source and it passes 
all the self tests. I have installed DBI-1.5 and it passes all the tests. I can 
compile DBD::mysql (v 3.0002) but the test fails:

t/mysql2.............Mysql connect('database=test;host=','',...) failed: Can't 
connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) at 
t/mysql2.t line 29

This is a puzzler, because the output from mysql_config is:

[root@HSV-PROBE DBD-mysql-3.0002]# mysql_config
Usage: /usr/local/mysql/bin/mysql_config [OPTIONS]
Options:
        --cflags         [-I/usr/local/mysql/include/mysql]
        --include        [-I/usr/local/mysql/include/mysql]
        --libs           [-L/usr/local/mysql/lib/mysql -lmysqlclient -lz 
-lcrypt -lnsl -lm]
        --libs_r         [-L/usr/local/mysql/lib/mysql -lmysqlclient_r -lz 
-lpthread -lcrypt -lnsl -lm -lpthread]
        --socket         [/tmp/mysql.sock]
        --port           [3306]
        --version        [5.0.21]
        --libmysqld-libs [-L/usr/local/mysql/lib/mysql -lmysqld -lz -lpthread 
-lcrypt -lnsl -lm -lpthread -lrt]

/etc/my.cnf also points to /tmp/mysql.sock.

I tried hardwiring the socket in the make with perl Makefile.PL 
--testsocket=/tmp/mysql.sock and the tests _still_ try to use 
/var/lib/mysql/mysql.sock.

Does anybody have any ideas why DBD::mysql is so fixated on the wrong socket 
path?

Thanks

Mike