Is there currently any easy way to set up a YAWS web server in front of Apache Tomcat Servlet container, similar to popular Apache httpd + Tomcat set up?
I do not believe there is an AJP connector for YAWS, but you should be able to front Tomcat with YAWS via HTTP. YAWS is relatively easy to setup as a reverse proxy. See the man page here for details (see revproxy):
http://yaws.hyber.org/yman.yaws?page=yaws.conf
Note: This is not yet considered production quality so you will want to do plenty of testing to ensure this satisfies your production requirements.
I do not know what your use case is, but you may find Nginx is a worthwhile alternative to Apache as a load-balanced, HTTP reverse proxy in front of Tomcat. There are a number of good tutorials for this on the web, or checkout the recent Linux Journal article (requires a subscription):