Replication error

[Hub D.]

Hi!

I am puzzled.

I have a nameserver that uses a MySQL database as backend.

On my masterserver ( RH 7.3, MySQL release 3.23.58-log ) I have a web panel for adding data to the database.
I have setup replication with my second nameserver ( FC 2, MySQL release 3.23.58 ), that acts as first slave.

This combo works fine.

Now I want to add a second replication slave. And yes, I run into problems.
This server is a FC 4 with MySQL release 4.1.12-log.

When I start MySQL I get this error:
050930 2:34:58 [ERROR] Slave I/O thread: error connecting to master 'user@some_ip:3306': Error: 'Can't connect to MySQL server on 'some_ip' (13)' errno: 2003 retry-time: 60 retries: 86400

When I type 'telnet some_ip 3306' I see the MySQL-prompt. So, the connection is ok.

I read somewhere that a newer MySQL-release as master and an older MySQL-release as slave is not possible. But this combo (old master, new slave) should be possible.

This is the my.cnf of the master:

[mysqld]
log-bin
server-id=1
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
skip-innodb
set-variable=max_allowed_packet = 128M

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

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

And this is the my.cnf of the second slave (that gives the error):

[mysqld]
safe-show-database
innodb_data_file_path=ibdata1:10M:autoextend
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
skip-innodb
#set-variable=max_allowed_packet = 128M
old_passwords=1
server-id=3
master-host=some_ip
master-port=3306
master-user=user
master-password=pass
master-connect-retry=60 # num of seconds, default is 60
replicate-do-db=pdns
log-slave-updates
log-bin

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

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


Like the first slave (that works!) I have granted user on some_ip only File rights.

Any anybody help me? This is driving me mad.

Cheers

H.