[Mediawiki-l] Image convert problem with .jpg files?

[Niedziela, Jennifer]

Running 1.9.1.  When a user attempts to change the size of a *.jpg file (via [[Image:filename.jpg|thumb|Description]], an error is created reading: "Permission denied convert: no decode delegate for this image format ... missing an image filename".

This works just fine for  *.gif files.  Any ideas?

Thanks,
Jen