Database error Problem

[King Diamond]

Hello, I'd like to know how to fix this "database error" problem, 'cause when the number of online users gets high, this error starts happening in any thread, portal, in the admincp, etc. Then I check the source-code and it the errors is the following:

Database error in vBulletin :

mysql_connect() [<a href='function.mysql-connect'>function.mysql-connect</a>]: User forum_forum already has more than 'max_user_connections' active connections
/home/sued576/public_html/includes/class_core.php on line 311

MySQL Error :
Error Number :
Request Date : Tuesday, March 24th 2009 @ 02:06:34 PM
Error Date : Tuesday, March 24th 2009 @ 02:06:34 PM
Script : http://www.mysite.org/index.php
Referrer :
IP Address : 201.89.145.35
Username :
Classname : vB_Database
MySQL Version :
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