Same issue here today. Running PHP 5.4 with OPcache and Zend Optimizer enabled on a cPanel box.
Getting these suddenly:
connection to [/tmp/lshttpd/lsphp5.sock.780] on request #1, confirmed, 1, associated process: 4791, running: 1, error: Connection reset by peer!
Running LT 4.2.10
config...