GDAL/JPEG driver in MapServer 5.2.x fails

[jratike80]

With Mapserver versions 5.2.0, 5.2.1 and 5.3-dev on Windows XP and obtained from MS4W and FWTools packages, having the following outputformat in mapfile leads to error:

   OUTPUTFORMAT
      NAME "jpeg"
      MIMETYPE "image/jpeg"
      DRIVER "GDAL/JPEG"
      EXTENSION "jpg"
      IMAGEMODE RGB
    END

The error, captured from ms errorfile is:

[Tue Mar 17 14:03:47 2009].478000 msSaveImageGDAL(): 
General error message. Failed to create output JPEG file.
JPEG driver doesn't support 4 bands.  
Must be 1 (grey) or 3 (RGB) bands.

Simple mapfile is included.

[jratike80]

MS mapfile that gives an error