We have a server located at a local company's place of business running Solaris/Apache/PHP. They recently did an update to Solaris, Apache, and PHP (security update patches, etc.). Unfortunately it has caused the image manipulation portion of our software to break. imagecreatefromjpeg() is now generating the following error:

Warning: imagecreatefromjpeg() [function.imagecreatefromjpeg]: '/path/to/file/filename.jpg' is not a valid JPEG file in /path/to/file/Image.class.php on line XX

No PHP code was changed during the server upgrade and it was fully functional before the software upgrades. I checked the files being passed to imagecreatefromjpeg() and they are indeed valid (they open successfully in both image editing software and in my browser). I checked the permissions of the directory from which the files are being opened and they do have read permission. GD library is enabled.

I'm not sure what else I can check. Based on the scenario above I am guessing something changed in the software but I don't know what it could be. PHP was version 5.2.5 and is now 5.2.13.

I appreciate any guidance as to what could be cause of this issue.