Mysql replication - Error No. 1146&1062
I did as described here and it solved my problem.
So basically I added the following to [mysqld] section in my.cnf files:

Master-1:

server-id = 1
replicate-same-server-id = 0
auto-increment-increment = 2
auto-increment-offset = 1


Master-2:

server-id = 2
replicate-same-server-id = 0
auto-increment-increment = 2
auto-increment-offset = 2