ECW Image Shift

[Eric Lowrance]

Hi all,
I have about 30 tiled ECW images in WGS84 that exhibit a x-shift of about
50m when compared to the originals and other WGS84 map services (Like
Terraserver) and other data sources.  This same shift appears in both my
web browser application and ArcMap, so it seems as if MapServer or my
configuration is the culprit.  If I bring one of the tiled images in ArcMap
it lines up just fine with all of my other data sources.  I'm a MapServer
novice, so any suggestions would be appreciated, thanks!

MAP
  NAME NATURALVIEW
  IMAGETYPE png24
  EXTENT -126.001390 39.99844 -107.99847 55.00139
  SHAPEPATH "W:\data\NVECW\"
 OUTPUTFORMAT
    NAME PNG24
    DRIVER "GD/PNG"
    MIMETYPE "image/png"
    EXTENSION PNG
    IMAGEMODE RGBA
    TRANSPARENT ON
 END

  WEB
    METADATA
      WMS_TITLE "NaturalVue_Imagery"
      WMS_ONLINERESOURCE "http://..."
      WMS_SRS "EPSG:4326"
    END
  END


  # Start of LAYER DEFINITIONS ---------------------------------------------

  LAYER
    NAME "NaturalVue"
    METADATA
     "wms_title" "NaturalVue_Imagery"
     "wms_srs"             "EPSG:4326"
     "wms_name"            "NaturalVue"
     "wms_server_version"  "1.1.1"
     "wms_formatlist"      "image/jpeg image/png24"
     "wms_format"          "image/png"
    END
    STATUS ON
    TILEINDEX "nv_index.shp"
    TILEITEM "location"
    TYPE RASTER


END