net/tcpdump doesn't link itself against installed net/libsmi

[Mikhail]

$ sudo portversion -v libsmi                                                           20:36 ttyp1
libsmi-0.4.2                =  up-to-date with port
$ more /usr/local/etc/pkgtools.conf
 MAKE_ARGS = {
 'net/tcpdump' => 'TCPDUMP_OVERWRITE_BASE=yo WITH_RADIOTAP=yo WITH_TCPMD5=yo',
 'net/libpcap' => 'LIBPCAP_OVERWRITE_BASE=yo',
}
$ sudo portinstall -Rrf net/tcpdump
++++++ skip ++++++++
checking smi.h usability... no
checking smi.h presence... no
checking for smi.h... no
checking for smiInit in -lsmi... no
++++++ skip ++++++++
$ ldd `which tcpdump`
/usr/sbin/tcpdump:
        libpcap.so.2 => /usr/lib/libpcap.so.2 (0x280c3000)
        libc.so.4 => /usr/lib/libc.so.4 (0x280ea000)
$ sudo tcpdump -i bfe0 -m /usr/local/share/smi/mibs/iana/IANA              
tcpdump: ignoring option `-m /usr/local/share/smi/mibs/iana/IANA' (no libsmi support)