mail/p5-Mail-ClamAV fails to build

[Gregory Orange]

I'm trying to build mail/p5-Mail-ClamAV and getting this error:

/usr/local/bin/perl /usr/local/lib/perl5/5.14/ExtUtils/xsubpp  -typemap 
"/usr/local/lib/perl5/5.14/ExtUtils/typemap"  ClamAV.xs > ClamAV.xsc && 
mv ClamAV.xsc ClamAV.c
cc -c 
-I"/var/obj/usr/ports.local/mail/p5-Mail-ClamAV/work/Mail-ClamAV-0.29" 
-DAPPLLIB_EXP="/usr/local/lib/perl5/5.14/BSDPAN" -DHAS_FPSETMASK 
-DHAS_FLOATINGPOINT_H -fno-strict-aliasing -pipe -fstack-protector -O2 
-pipe -fno-strict-aliasing    -DVERSION=\"0.29\"  -DXS_VERSION=\"0.29\" 
-DPIC -fPIC "-I/usr/local/lib/perl5/5.14/mach/CORE"   ClamAV.c
ClamAV.xs:11:20: error: clamav.h: No such file or directory

There is more, but being unable to find clamav.h seems to be problem 
enough, and the other errors look related to this.

security/clamav is installed, and /usr/local/include/clamav.h is 
present. A friend built it successfully on his machine, and gave me a 
screen grab. The only difference is that line, which also has 
"-I/usr/local/include" - which I think would make it work.

I see /usr/ports/Mk/bsd.database.mk has this line:
CPPFLAGS+=              -I${LOCALBASE}/include

and /usr/ports/Mk/bsd.port.Mk has this line:
bsd.port.mk:LOCALBASE?=         /usr/local

but I don't know how and where these would be used.

What should I do next, to troubleshoot this?

TIA,
Greg.