I think I just encountered some nasty bug in SCGI. The code in Quixote
application causes this error (see subject) in the scgi log. After
that communication between SCGI and Apache seems to be broken, and
only restarting SCGI process and Apache seems to help.

This is the part of the code when it probably happens:
           fullname = join(IMAGES_DIR, filename)
            print ">>>", fullname
            print ">>>", filename
            size = getsize(fullname)
            print ">>>", size
            request.response.set_header('Content-Disposition',
'attachment; filename=%s' % (filename,))
            request.response.set_header('Content-Length', size)
            return StaticFile(fullname, mime_type='application/force-download')

Actually, it was working till today... I am going to test now and try
to find what exactly causes the error...
BTW, is there any way to determine mod_scgi version from binary? I
think I've accidentally deleted the source directory :(((

Thanks!
--
Ksenia