graphics/opencv ISSUE with gcc 4.6.3

[awarecons]

===>  Building for opencv-2.3.1_5
[  1%] Generating opencv_calib3d_pch_dephelp.cxx
Scanning dependencies of target opencv_calib3d_pch_dephelp
[  1%] Building CXX object
modules/calib3d/CMakeFiles/opencv_calib3d_pch_dephelp.dir/opencv_calib3d_pch_dephelp.o
Linking CXX static library ../../lib/libopencv_calib3d_pch_dephelp.a
[  1%] Built target opencv_calib3d_pch_dephelp
Scanning dependencies of target pch_Generate_opencv_calib3d
[  1%] Generating precomp.hpp
[  2%] Generating precomp.hpp.gch/opencv_calib3d_Release.gch
/usr/lib/crt1.o: In function `_start1':
crt1_c.c:(.text+0x9d): undefined reference to `main'
collect2: ld returned 1 exit status
*** Error code 1

Stop in /usr/ports/graphics/opencv/work/OpenCV-2.3.1.
*** Error code 1

But gcc 4.2+ works fine. Wonder, if there's need of libmap or so?