Problem with MySQL Master/Slave reboot when in replication
Step 01) STOP SLAVE; on all Slaves
Step 02) service mysql stop on the Master
Step 03) Reboot Master
Step 04) For each Slave


Reboot each Slave
If /etc/my.cnf has skip-slave-start, then run START SLAVE;

Step 05) Check that each Slave is fully running


Run the following on the command line

SLAVETHREADCOUNT=`mysql -u... -p... -AN -e"SHOW PROCESSLIST" | grep -c "system user"`
echo ${SLAVETHREADCOUNT}


If SLAVETHREADCOUNT is 2, replication is fully operational.

Give it a Try !!!