It's about MySQL Database. I just want to know how can I prevent from
getting many "Sleep" command processes which can be much longer than
300 (Time). Sometime I can have much than 10 processes with "Sleep"
command longer than 500 (Time).

Your typical dialog should

open,
work with,
and close

connections. If you do not close them, they persist.
example:

----------------------------------\\
<?php
//Open connection
    $db2 = mysql_connect($host, $dabu, $dabap);
    mysql_select_db($dab,$db2);

process your querries

AND 

// Close MySQL Connection
mysql_close($db2);
?>
--------------------------------//

detailed example:

http://dev.mysql.com/doc/refman/5.0/en/dao--rs-addnew.html

manual
http://cz2.php.net/function.mysql-pconnect
http://helpguide.inmotionhosting.com/php_faq/function.mysql-close.html

the "sleep" status processes you see in your mysql, is a connection
made to your database from (my guess) a web server and probably an
apache web server.

note that the amont of "idle connections" (or sleep commands as you
call them) cannot crash the mysql or overload it, the only problem
that might happen is reaching the maximum opened connections you allow
to your mysql.

by default php will use persistent connections to you mysql which
means, that it will first try to use an existing connection for a new
database access, if not it will open a new one, since apache use
different threads it will allways open a new connection while the
other one is idle and it cannot use that one.

you can minimize it by not allowing persistent connections in your php.ini file

[MySQL]
; Allow or prevent persistent links.
mysql.allow_persistent=Off

and restart you web server daemon.

this way the conection "SHOULD" be closed after the script has finished running.

hope it helps
lior