Symbols and Imagemode RGB/RGBA

[Lars-G öran Edholm]

I have problem with symbols in Mapserver 4.
In Mapserver 3 I'm using IMAGEMODE RGBA with symbol "downwarddiagonalfill".
In Mapserver 4 I cant get an Transparent fill, I always get a grey
background which is the same as IMAGECOLOR for the whole map.
Also I cant change the backgroundcolor of the map, it is always gray.
I have been testing this with the Itasca demo but I cant get it to work.
I can get it to work with in my own application in IMAGEMODE PC256 but then
I cant use colored ortophotos because blue lakes in my waterlayer become
green. If i have yellow lakes theres no problem.
Whats the problem in Mapserver 4?
MAP
  NAME ITASCA
  IMAGECOLOR 255 255 0  #Cant change, its always gray
.
.
IMAGETYPE pnglge
.
.
.
OUTPUTFORMAT
  NAME pnglge
  DRIVER "GD/PNG"
  MIMETYPE "image/png"
  IMAGEMODE RGBA
  EXTENSION "png"
END
.
.
.
SYMBOL
  NAME "downwarddiagonalfill"
  TYPE vector
  TRANSPARENT 0
  POINTS
    0 1
    1 0
  END
END
.
.
.
LAYER
    NAME lakespy2
    TYPE POLYGON
    STATUS OFF
    DATA lakespy2

    CLASS
      NAME 'Lakes & Rivers'
      TEMPLATE "templates/lakespy2.html"
      STYLE
      color 0 255 0   #should be green with underlaying layers as background
      size 5
      symbol "downwarddiagonalfill"
      END
    END


 Mvh
Lars-Göran Edholm    tel 026/24 14 36
1:e byggnadsinspektör
Bygg- och miljökontoret
811 80 Sandviken
lars-goran.edholm at sandviken.se