Sub Domains – WP Multi Site Local Install

Hi,

I was hoping someone could help me with this:

I have WordPress 3.5 set up locally on my machine using XAMPP.
After enabling WordPress multi-site, I get the following message in my Network Setup panel:

• Sub-directory Install -> Because your install is in a directory, the sites in your WordPress network must use sub-directories.
• Server Address -> The internet address of your network will be wordpress.dev.

My end goal is to have my URLs set up using subdomains like so:
site1.wordpress.dev, site2.wordpress.dev.

I want to understand why WordPress MS isn’t giving me the option of setting up my network using subdomains.

Normally one would have this problem if their server address was simply “localhost/…” or an IP, but mine is set up as a domain wordpress.dev.

Note: I’ve done this successfully in the past with WordPress 2.8, the problem surfaced once I upgraded to WP 3.5.

Any help would be greatly appreciated.