On IBM AIX 5.3, if you are running the web agent for IBM HTTP Server based on Apache HTTP Server 2.0.x, the server sometimes crashes at startup.
Workaround. Upgrade the AIX bos.rte.libc fileset from Service Pack 7 to Service Pack 9 (AIX 5.3.0.68 to 5.3.0.70). For information see:
http://www-01.ibm.com/support/docview.wss?uid=isg1fileset-870201775