MySQL Max Connections

My PHP application is starting to reach max mysql server user connections limit (currently set to 60). I listed mysql process list in phpmyadmin and found there lot of queries with status "LOCKED" these hang there for a long time(not always just sometimes - twice a day) and then connection limit is reached. It causes load average about 40 for as long as 10 - 20 minutes

I think it may be bacause of query structure. There are some queries with many inner joins...

Here is typical situation from phpmyadmin's process list:

1. select ... from table_1
inner join table_2
inner join table_3
inner join table_4
inner join table_5
This show status : "Copying to tmp table" in phpmyadmin

2. update table_2 set ....

This shows status: Locked

3. select ... from table_2

This shows status: Locked

Seems then when temp table is being created the table_2 is locked and it cannot make update to table_2. or maybe it's locked because of just that update on table_2.

I want to avoid of creating temp tables... Can it help if I'll make separate selects without large table joins ?