`php -v` segmentation fault

Question

I'm getting an odd segmentation fault in PHP. Every few times, when I run:

php -v

I see:

PHP 5.2.6 (cli) (built: Aug 19 2009 16:59:56) 
Copyright (c) 1997-2008 The PHP Group
Zend Engine v2.2.0, Copyright (c) 1998-2008 Zend Technologies
Segmentation fault (core dumped)

Analyzing the core dump (backtrace with gdb):

#0  0x00002ba6412f6c6c in ?? ()
#1  0x0000003f90c06367 in start_thread () from /lib64/libpthread.so.0
#2  0x0000003f904d2f7d in clone () from /lib64/libc.so.6
#3  0x0000000000000000 in ?? ()

Any ideas?

Linux version 2.6.18-92.el5 ([email protected]) (gcc version 4.1.2 20071124     
(Red Hat 4.1.2-42)) #1 SMP Tue Jun 10 18:51:06 EDT 2008