Separate hostname on same CI site

[eluser]Unknown[/eluser]
I've been reading various articles on setting up multiple sites with the same CI codebase, but I'm a bit lost in the competing options so I just thought I'd ask.

Here is the situation: I have a primary site at www.example.com. I need to develop a second set of (primarily view) pages on a second hostname, such as simple.example.com, which will be basically the same website but more of a "lite" version of the original. 90% of the site will be the same code, especially the models. (This is all on one machine.)

One option is to create a second site and just symlink the files, but I'm using SVN and I really don't want to treat them separately because that's going to cause problems checking in/out code. What I really thought about doing is creating a controller in my primary site called simple.php and then using mod_write to point simple.example.com to www.example.com/simple since this needs to be hidden from the user (the user of the simple site should not see the real www.example.com site or really be aware it's there.)

I looked at the user guide on multiple sites with one CI installation, but it looked like it was actually using two separate sets of models/views etc, which isn't what I want.

Any opinions on what would be best?