I've attached a patch that allow the compilation (and installation) of
the jpeg plugin. It uses a GtkTextView/GtkTextBuffer couple instead of
the deprecated GtkText for the image comment.
Well, to use this patch, you'll also have to remove the '#' in front
of the jpeg plugin definition in plugin-defs.pl, and re-run mkgen.pl.
The patch works OK. I've tested it, and I'm happy to see this plugin
Now that I know how to do this, and if my patch is good enough, I could
fix the other plugins if you want to. Just tell me.