make[1]: Entering directory `/var/www/nagios-plugins-1.4.16/plugins'
gcc -DLOCALEDIR=\"/usr/local/icinga/share/locale\" -DHAVE_CONFIG_H -I. -I.. -I.. -I../lib -I../gl -I../intl -I/usr/include -DNP_VERSION='"1.4.16"' -g -O2 -MT check_http.o -MD -MP -MF .deps/check_http.Tpo -c -o check_http.o check_http.c
check_http.c: In function 'process_arguments':
check_http.c:312:9: error: 'ssl_version' undeclared (first use in this function)
check_http.c:312:9: note: each undeclared identifier is reported only once for each function it appears in
make[1]: *** [check_http.o] Error 1
make[1]: Leaving directory `/var/www/nagios-plugins-1.4.16/plugins'
make: *** [install-recursive] Error 1


To solve this make sure you have libssl-dev package installed.

apt-get install libssl-dev

./configure \
--prefix=/usr/local/icinga --with-cgiurl=/icinga/cgi-bin \
--with-nagios-user=icinga --with-nagios-group=icinga
make && make install