External link warning

[TheGorf]

I'm not sure I know how to communicate exactly what I am looking for in an "easy to search" way so pardon if this is a well known issue.

Are there any settings or mods for vB such that when a user clicks on a link that takes them off the forum it first provides a warning that they are about to leave the forum site and go to an external website we have no control over? I am thinking something similar to what CNN does.

Thanks