Can one make Eye of Gnome detect file type rather than use suffix?

[Chris Green]

In general Linux ignores file suffixes like .jpg and .png to identify
file types as it uses the magic number within the file itself.
However Eye of Gnome seems to use the suffix which is a bit of a
nuisance (I just got some images mailed to me which had suffix JPG but
were actually PNG files).

File viewers like ristretto ignore the suffix and can view the files
OK but Eye of Gnome outputs an error.  I want to use Eye of Gnome for
its printing ability.

Is there any way I can make Eye of Gnome ignore the file suffix and,
instead, use the magic number?

-- 
Chris Green