Image Upload adding Text

When I upload an image, it adds some funky text to the bottom of my image. I can’t read what it says, and it doesn’t do it all the time, but it’s driving me crazy. Here is a screenshot of the image:

I created this image myself, and when I view it on my PC that funky text is not on the image. It happens when I upload via WordPress.

I was able to get around it by uploading the image via FTP and inserting it via the HTML interface, but just wondered if anyone had ever seen this one?

I’m using 2.5 and firefox