[SOLVED] Facebook links to my site resolve as 403 forbidden

Facebook links to my site resolve as 403 forbidden

Hi I'm experiencing a super weird problem.
Whenever I post links to my website on Facebook, they come up as Forbidden.
The site itself works great and I have no seen this when linking on other sites.
Could this be a server misconfiguration? Any thoughts on where to look?

here's some Info:
I have a dedicated server running WHM 11.25.0
i have 2 sites hosted here using cPanel 11.25.0

the error msg:

Forbidden

You don't have permission to access /blog/deepwater-horizon-11/ on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

Apache/2.2.14 (Unix) mod_ssl/2.2.14 OpenSSL/0.9.8i DAV/2 mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 Server at www.offshoreinjuries.com Port 80

UPDATE:
Here is a sample link if it helps. (notice going the linked page directly works fine)
http://www.facebook.com/l.php?u=http%3A%2F%2Fwww.offshoreinjuries.com%2Fblog%2Fdeepwater-horizon-11%2F&h=834ea

UPDATE and ANSWER:
Found the issue and added a complete answer below.

Solution

I was finally able to get to the bottom of this behavior.
The default mod_security settings of my host, HostGator include a set of whitelists and blacklists. Upon inspecting these I found .facebook.com/l.php blacklisted.
l.php is a wrapper page that provides a warning that you are leaving facebook. As I understand it since this can be easily exploited, HostGator chose to essentially blacklist all outbound facebook links.

I fixed my problem by removing .facebook.com/l.php from the mod_security blacklist, however I could have also just reset my mod_security settings to Default (vs the HostGator config) via a single click in WHM.