Lost transparency for diagonal fill by changing from 4.0.1 to MapServer 4.4.0-beta1 a.o.

[Janeks Kamerovskis]

This problem appears, when I am using imagetype PNG24.
When I am using JPEG, then images does not appears in my Web template.
I checked tmp dir, there was some *.jpg files, but when I tried to open them
with MS-PhotoEditor, then err. message: Can't determine type?

Here are map file part, that worked in 4.0.1.

    CLASS
      NAME 'name'
      STYLE
        SYMBOL 'downwarddiagonalfill'
        COLOR 225 51 0
        OUTLINECOLOR 255 0 255
        SIZE 5
      END
    END

Symbol:

SYMBOL # Downward diagonal fill
  NAME "downwarddiagonalfill"
  TYPE vector
  TRANSPARENT 0
  POINTS
    0 1
    1 0
  END
END

What could be a reason?

Janeks