Easy way to run several ColdFusion instances using one apache server

As you might know, in the server configuration JRun is the J2EE server in the background of CF and so in the apache configuration you will notice that the whole connector stuff is done using JRunConfig* directives.
As long as only one version of CF is running using apache as webserver everything is fine, it starts getting complicated when you decide to run e.g. 7 and 8 on one machine using one apache instance. Here you can find a solution how to set it up with different JRun ports which I did once as well (took me hours to find out all these stuff ;-)).
A very nice, quick and dirty solution I came accross some time ago is to use the power of mod_proxy - in this case you tell apache to forward all requests to a different port / URL whatever.
So I did the following:

• Set up CF 7
• Connect CF 7 to apache using the default way
• Set up CF 8 using the internal web server
• Enabled mod_proxy in apache (AddModule / LoadModule)
• Added the following lines in my virtual host configuration for a CF8 host:
  ProxyRequests on
  ProxyPass / http://127.0.0.1:8500/
• Worked!

Of course this is not a proper solution for deployment but for development purporses it's great. Using this way all apache modules and configuration possibilites (e.g. mod_rewrite, mod_deflate, access control) can be used and the internal webserver of CF is just the dummy backend.