Mysql Database Expert Needed

I have a large social network style website with many users. Currently there are lots of sleeping queries which keep mysql pegged at 100% cpu usage. The server load is pretty low and appears to have plenty of CPU/RAM/IO left to spare, but the trouble seems to be with connections not closing properly, I need a mysql expert that can fully review and optimize the database. The database is custom developed so it is important that any changes made are carefully considered. Please only apply if you are an expert in mysql and have a great deal of experience in optimization. Here is an example of the latest mysql usage log: root@server1 [~]# mysqladmin processlist +----------+----------------+-----------+--------------+---------+------+-------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----------+----------------+-----------+--------------+---------+------+-------+------------------+ | 29931815 | leechprotect | localhost | leechprotect | Sleep | 1624 | | | | 29932034 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 1534 | | | | 29935325 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 1175 | | | | 29935956 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 1092 | | | | 29939275 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 321 | | | | 29939551 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 623 | | | | 29941286 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 392 | | | | 29941389 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 378 | | | | 29941458 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 369 | | | | 29942002 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 192 | | | | 29942414 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 251 | | | | 29942666 | eximstats | localhost | eximstats | Sleep | 0 | | | | 29943000 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 178 | | | | 29943204 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 156 | | | | 29943250 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 149 | | | | 29943385 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 134 | | | | 29943544 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 115 | | | | 29943850 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 75 | | | | 29944368 | mpsadmin_user1 | localhost | mpsadmin_555 | Sleep | 5 | | | | 29944409 | root | localhost | | Query | 0 | | show processlist