[root@gw-server /usr/ports/www/mod_security2]# make install clean
===>  Building for mod_security2-2.1.0
===>  Generating apache plist
/usr/local/build-1/libtool --silent --mode=compile cc -prefer-pic -O2 -fno-strict-aliasing -pipe    -I/usr/local/include/apache22  -I/usr/local/include/apr-1   -I/usr/local/include/apr-1 -I/usr/local/include  -c -o apache2_config.lo apache2_config.c && touch apache2_config.slo
In file included from modsecurity.h:37,
                 from apache2_config.c:15:
msc_pcre.h:18:18: pcre.h: No such file or directory
apache2_config.c: In function `cmd_audit_log_relevant_status':
apache2_config.c:583: error: `PCRE_DOTALL' undeclared (first use in this function)
apache2_config.c:583: error: (Each undeclared identifier is reported only once
apache2_config.c:583: error: for each function it appears in.)
apxs:Error: Command failed with rc=65536
.
*** Error code 1

Stop in /usr/ports/www/mod_security2.
[root@gw-server /usr/ports/www/mod_security2]#