Its been a long time since I used solaris, but "file core" might tell you the program that caused the core dump.
A debugger will allow you to get a stack trace at the time of the crash. For dbx (one of the debuggers available on Solaris) the commandline would be: dbx httpd core (use pathnames for the two arguments). The debugger will complain if the exexutable program and the core file don't match. In dbx the command to print a stack trace is "where" which often is all you need. If you don't have dbx try adb (absolute debugger) or mdb (modular debugger).--
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