MOD_JK and JCIFS on Linux platform

Hi,

I am trying to implement Single Sign On for a web application. To do so
I'm using JCIFS.

I first did some test using on Windows XP platform:
apache 2.0.54
jakarta tomcat 5.5.4
mod_jk 1.2.14 for apache 2.0.54
jdk 1.5.0

It worked like a charm.

Then I went on to try the same solution on a RedHat Linux environment
(All our web/app servers are Linux machines).
Linux 2.4.20-8smp
Apache build: httpd-2.0.47-10
Mod_jk version: mod_jk-ap13-1.2.4-1jpp
Tomcat 5.5.4
jdk 1.5.0

This time, I couldn't even access the pages, but I could see SSO
working when I was going straight to the Tomcat port.

I then installed Fedora on my development PC and started to
investigate. I obviously had the same problem on Fedora than I had on
the Linux server:
Linux 2.6.11-1.1369_FC4
Apache/2.0.53-dev
Tomcat 5.5.4
I eventually managed to make the whole thing work by recompiling apache
with mod_jk.

So the first question:
Would anyone know why I have to recompile mod_jk with apache on Linux
when the solution worked fine on XP?

Second question:
Is this a bug/flow in design from apache or mod_jk for Linux?

Note: due to maintenance aggreement and company security policy,
recompiling apache and mod_jk is not an acceptable solution for me.
Also, even though the solution works fine on apache 2.2.0, I can't use
it since this version is not yet supported by RedHat.

Many thanks
Yannick