What does glibc detected ...httpd: double free or corruption mean?

I have asked this question on serverfault.com which is as suggested a more appropriate place for it - https://serverfault.com/questions/169829/what-does-glibc-detected-httpd-double-free-or-corruption-mean

I have an EC2 server running that I use to process image uploads. i have a flash swf that handles uploading to the server from my local disk - while uploading about 130 images (a total of about 650MB) I got the following error in my server log file after about the 45th image.

* glibc detected * /usr/sbin/httpd: double free or corruption (!prev): 0x85a6b990 ***

What does this error mean?

The server has stopped responding so 开发者_开发知识库I will restart it. Where should I begin to find the cause of this problem?

thanks

some info -

Apache/2.2.9 (Unix) DAV/2 PHP/5.2.6 mod_ssl/2.2.9 OpenSSL/0.9.8b configured Fedora 8

This means your web server has crashed. Barring bad hardware, this is a bug inside either the Apache server or a module you have loaded (such as mod_php).

Try upgrading to a newer version, if one is available. If that fails, open a bug report with the Apache maintainers.