Build Universal Apache Tomcat Connector (mod_jk) for OSX follow tricks used for Apache Tomcat Native Library.

CFLAGS='-arch i386 -arch x86_64' APXSLDFLAGS='-arch i386-arch x86_64'

Here is a small script to do it :

#!/bin/sh
#

JK_VERSION=1.2.37

curl http://mir2.ovh.net/ftp.apache.org/dist/tomcat/tomcat-connectors/jk/tomcat-connectors-${JK_VERSION}-src.tar.gz -o tomcat-connectors-${JK_VERSION}-src.tar.gz
tar xvzf tomcat-connectors-${JK_VERSION}-src.tar.gz
cd tomcat-connectors-${JK_VERSION}-src/native

./configure --with-apxs=/usr/sbin/apxs CFLAGS='-arch i386 -arch x86_64' APXSLDFLAGS='-arch i386-arch x86_64'
make clean
make

Installation is pretty simple :

sudo cp apache-2.0/.libs/mod_jk.so /usr/libexec/apache2/

You could then restart your Apache HTTPd server to get new mod_jk used :

sudo /usr/sbin/apachectl restart