Wgrib2 for FreeBSD

[Valerio Guerra]

Hi All,
I tried to compile wgrib2 on FreeBSD 6.1 without success.
The following is the error I obtain on the 'make'

> dec_png.c:117: error: `PNG_COLOR_TYPE_RGB_ALPHA' undeclared (first use in this function)
> *** Error code 1
>
> Stop in /usr/home/grib2/g2clib-1.0.5.
> *** Error code 1
>
> Stop in /usr/home/grib2.
> $

The system already has both png and zlib libraries.
Any ideas, suggestions?
Where can I find a Wgrib2 binaries for FreeBSD?

Thank you.

Valerio Rossi.