Today I tried to setup a Java web application on an Ubuntu 7.04 system. This means installing apache web server, Tomcat and configuring mod_jk. I have done this many times before but this time there was something different: the default version of apache that comes with Ubuntu 7.04 is 2.2.x – until today I only used apache 2.0.x with mod_jk and tomcat.

After installing the JDK, Tomcat and apache I downloaded the source of mod_jk from the Tomcat Connectors download site. After unpacking it and running

configure --with-apxs=/usr/bin/apxs2

I tried to run make and the following error occured:

Making all in common
make[1]: Entering directory `/home/user/downloads/tomcat-connectors-1.2.23-src/native/common'
/usr/share/apr-1.0/build/libtool --silent --mode=compile gcc -I/usr/include/apache2 -g -O2 -DLINUX=2 -D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_REENTRANT -I/usr/include/apr-1.0 -I/usr/include/openssl -I/usr/include/postgresql -I/usr/include/xmltok -pthread -DHAVE_APR -I/usr/include/apr-1.0 -I/usr/include/apr-1.0 -g -O2 -I /include -I /include/ -c jk_ajp12_worker.c -o jk_ajp12_worker.lo
libtool: compile: unable to infer tagged configuration
libtool: compile: specify a tag with `--tag'
make[1]: *** [jk_ajp12_worker.lo] Error 1
make[1]: Leaving directory `/home/user/downloads/tomcat-connectors-1.2.23-src/native/common'
make: *** [all-recursive] Error 1

I did some research and found this nice site providing a solution to this problem. As the error message says I had to add the --tag parameter to the libtool command. In my case the value to use was CXX – it is printed out when running configure.

After manipulating Makefile and common/Makefile by adding the parameter in the libtool line I was able to run make successful.

Now some could say “Why didn’t you install the mod_jk binary from the Ubuntu repositories?” – because the provided version 1.2.18 is very old and has some serious security issues.