UBB only allows a very limited subset of legit file extensions.
It' true ".jpeg" is a legit file extension, and came before ".jpg." It was truncated to ".jpg" early on because of MS Windows limitation of extensions to three characters - same reason ".html" was truncated to ".htm" so MS Windows machines could handle it.
Since UBB is an MS Windows-centric program, it was probably felt that including support for the legitimate but little used ".jpeg" extension was not necessary - or possibly the programmers doing the work did not even know that there were extensions of more than three characters - they are MS Windows types, after all. [img]/ubbthreads/images/graemlins/wink.gif[/img]
Anyway, since UBB looks at the file extension to validate for itself that it is indeed an image file, one must use a file extension UBB understands and permits or it will be rejected.
This means that if the file is already in use for other web pages or whatever, you're stuck. Since a file name already in use can't be changed for UBB's simple mind without breaking the other uses.
It is also unlikely that one can convince anyone able to add ".jpeg" to the list of image extensions allowed by UBB to actually do it.
Enjoy!
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(Interesting side note: The machine I'm typing this on recognizes 122 different extensions for images, and can display the images that use them.) </font>