Replication stops

I have 2 CentOS 5.5 servers runnig Mysql 5.5, configured as master-master replication. When on one server i have network problems, on another i see messages in log:

111105 2:38:30 [Note] Stop asynchronous binlog_dump to slave (server_id: 2)

when network problems gone, replication dont resume automatically, but it will start in a hour:

111105  3:37:41 [Note] Start binlog_dump to slave_server(2), pos(mysql-bin.000157, 344487149)
111105  3:37:41 [Note] Start asynchronous binlog_dump to slave (server_id: 2), pos(mysql-bin.000157, 344487149)

I think it is just configured timer, but which? Below is mysql configuration:
serv-01:

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
symbolic-links=0

plugin-load=archive=ha_archive.so;blackhole=ha_blackhole.so

#Replication
old_passwords=1
log-bin=/var/lib/mysql/mysql-bin
expire_logs_days=3
binlog-do-db=roomserv
binlog-do-db=asterisk
binlog-ignore-db=mysql
binlog-ignore-db=information_schema
server-id=1
auto_increment_increment= 2
auto_increment_offset   = 1

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

serv-02:

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
symbolic-links=0

#Replication
old_passwords=1
server-id=2

log-bin=/var/lib/mysql/mysql-bin
expire_logs_days=3
binlog-do-db=roomserv
binlog-do-db=asterisk
binlog-ignore-db=mysql
binlog-ignore-db=information_schema

#auto increment id offset
auto_increment_increment= 2
auto_increment_offset   = 2


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