I have spent some quality time today with moving a web application from a temporary development environment (Windows 2003 x86, IIS 6) to a production server (Windows 2008 R2 x64, IIS 7). The IIS-JBoss integration on the development servers has been set up based on mod_jk and worked without causing and troubles. However, reproducing the setup in the new environment was failing miserably. The first impression I am getting from IIS is that even logging is a science for itself, so it was even hard to determine why.
Luckily a forum post finally pointed me in the direction of Application Request Routing (ARR) module for IIS 7 as an alternative solution. Performance might be still a subject to be determined, but the installation and configuration is worlds cleaner compared to the mod_jk version.