/usr/ports/graphics/OpenEXR build error

[Joe Demeny]

Trying to upgrade /usr/ports/graphics/OpenEXR by following instructions 
in /usr/ports/UPDATING (20071008):

[root at beastie1 /usr/ports/graphics/OpenEXR]# make install
===>  Building for OpenEXR-1.6.0
Making all in config
gmake[1]: Entering directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/config'
gmake  all-am
gmake[2]: Entering directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/config'
gmake[2]: Nothing to be done for `all-am'.
gmake[2]: Leaving directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/config'
gmake[1]: Leaving directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/config'
Making all in IlmImf
gmake[1]: Entering directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/IlmImf'
if 
c++ -DHAVE_CONFIG_H -I. -I. -I../config -D_THREAD_SAFE -I/usr/local/include/OpenEXR -I.. -I../config   -pipe -O -pipe -MT 
b44ExpLogTable.o -MD -MP -MF ".deps/b44ExpLogTable.Tpo" -c -o 
b44ExpLogTable.o b44ExpLogTable.cpp; \
        then mv -f ".deps/b44ExpLogTable.Tpo" ".deps/b44ExpLogTable.Po"; else 
rm -f ".deps/b44ExpLogTable.Tpo"; exit 1; fi
b44ExpLogTable.cpp:52:18: half.h: No such file or directory
b44ExpLogTable.cpp: In function `int main()':
b44ExpLogTable.cpp:85: error: `half' undeclared (first use this function)
b44ExpLogTable.cpp:85: error: (Each undeclared identifier is reported only 
once for each function it appears in.)
b44ExpLogTable.cpp:85: error: expected `;' before "h"
b44ExpLogTable.cpp:86: error: `h' undeclared (first use this function)
b44ExpLogTable.cpp:90: error: `HALF_MAX' undeclared (first use this function)
b44ExpLogTable.cpp:114: error: expected `;' before "h"
gmake[1]: *** [b44ExpLogTable.o] Error 1
gmake[1]: Leaving directory 
`/usr/ports/graphics/OpenEXR/work/openexr-1.6.0/IlmImf'
gmake: *** [all-recursive] Error 1
*** Error code 2

Stop in /usr/ports/graphics/OpenEXR.

What am I missing?

This is a FreeBSD 5.5-STABLE system

-- 
Joe Demeny