Null image with WCS on 4.6.0 beta 2

[José Vicente Higón Valero]

Hi,
        here at gvSIG we're developing a WCS client on java, and we need to
serve some local quickbird 16bits tiff images with mapserver.

I've tryed to configure a mapserver 4.6.0 beta2 but have had no success.
At last I decided to simplify my problem, trying to replicate a
known-working configuration, that we've found at
'http://hypnos.cbs.umn.edu/cgi-bin/mapserv43d?'.

My map file is like this:

MAP
     NAME 'prueba_wcs'
     SHAPEPATH '/usr/local/mapserver/data'
     DEBUG ON
     IMAGETYPE PNG

     OUTPUTFORMAT
         NAME GEOTIFF_INT16
         DRIVER "GDAL/GTiff"
         IMAGEMODE INT16
     END

     OUTPUTFORMAT
         NAME GEOTIFF_RGB
         DRIVER "GDAL/GTiff"
         IMAGEMODE RGB
     END

WEB
     TEMPLATE "."
     METADATA
       "wcs_label" "Servidor pruebas wcs"
       "wcs_keywordlist" "WCS"
       "wcs_onlineresource" "http://gruposigp2/cgi-bin/wcs"
     END
     LOG "/usr/local/mapserver/wcs.log"
     IMAGEURL "/usr/local/mapserver/tmp/"
     IMAGEPATH "/usr/local/mapserver/tmp/"
END

PROJECTION
         "init=epsg:26915"
     END

LAYER
     NAME "prueba"
     TEMPLATE "."
     DEBUG ON
     STATUS OFF
     TYPE RASTER
     PROCESSING "SCALE=AUTO"
     UNITS METERS
     METADATA
       wcs_label "Cobertura prueba"
       ows_srs   "EPSG:26915"
       ows_extent "159707.000 4552995.000 1400707.000 5545795.000"
       wcs_resolution "500 500"
       wcs_formats "GEOTIFF_INT16 GEOTIFF_RGB"
       wcs_nativeformat "GEOTIFF_RGB"

       wms_title "prueba"
       wms_name "eso"
     END
     PROJECTION
         "init=epsg:26915"
     END
     DUMP TRUE
     DATA '/usr/local/mapserver/data/raster/prueba.tif'
   END
END


The gdalinfo's output of prueba.tif: (I got this coverage from the wcs
server hypnos.cbs.umn.edu with this request:
http://hypnos.cbs.umn.edu/cgi-bin/mapserv43d?map=/data/wcs/demo.map&
SERVICE=WCS&VERSION=1.0.0&REQUEST=GetCoverage&COVERAGE=ndvi&
TIME=2002-129&CRS=EPSG:26915&
FORMAT=GEOTIFF_INT16&RESX=500%200&RESY=500%200&
BBOX=159707.000000,4552995.000000,1400707.000000,5545795.000000):

Driver: GTiff/GeoTIFF
Size is 2482, 1986
Coordinate System is:
PROJCS["NAD83 / UTM zone 15N",
     GEOGCS["NAD83",
         DATUM["North_American_Datum_1983",
             SPHEROID["GRS 1980",6378137,298.2572221010042,
                 AUTHORITY["EPSG","7019"]],
             AUTHORITY["EPSG","6269"]],
         PRIMEM["Greenwich",0],
         UNIT["degree",0.0174532925199433],
         AUTHORITY["EPSG","4269"]],
     PROJECTION["Transverse_Mercator"],
     PARAMETER["latitude_of_origin",0],
     PARAMETER["central_meridian",-93],
     PARAMETER["scale_factor",0.9996],
     PARAMETER["false_easting",500000],
     PARAMETER["false_northing",0],
     UNIT["metre",1,
         AUTHORITY["EPSG","9001"]],
     AUTHORITY["EPSG","26915"]]
Origin = (159707.000000,5545795.000000)
Pixel Size = (500.00000000,-499.89929507)
Corner Coordinates:
Upper Left  (  159707.000, 5545795.000) ( 97d44'45.47"W, 49d58'2.20"N)
Lower Left  (  159707.000, 4552995.000) ( 97d 2'57.27"W, 41d 3'25.37"N)
Upper Right ( 1400707.000, 5545795.000) ( 80d34'20.14"W, 49d23'33.06"N)
Lower Right ( 1400707.000, 4552995.000) ( 82d21'28.87"W, 40d38'4.04"N)
Center      (  780207.000, 5049395.000) ( 89d24'38.67"W, 45d32'30.03"N)
Band 1 Block=2482x1 Type=Int16, ColorInterp=Gray

Finally, I write in a web browser:

http://172.19.21.36/cgi-bin/wcs&SERVICE=WCS&VERSION=1.0.0&REQUEST=GetCoverage&COVERAGE=prueba&CRS=EPSG:26915&FORMAT=GEOTIFF_INT16&RESX=500&RESY=500&BBOX=159708.000000,4552993.000000,1400706.000000,5545794.000000

but I receive a 0 bytes image.

May anyone help me?
Thanks in advance


PS: This tiff works fine in a wms request.


--
  José Vicente Higón
  gvSIG development Team
  Conselleria de Infraestructuras y Transporte
  Generalitat Valenciana
  Valencia - Spain
  http://www.gvsig.gva.es