Thats kind of funny!
Well the quick fix is in Subs.php, and the bug should effect urls, iurls and img tags as well. Anyway in that file search for
strpos($data, 'http://') !== 0 && strpos($data, 'https://') !== 0)
I think you will find it 6 times. Change that to
stripos($data, 'http://') !== 0 && stripos($data, 'https://') !== 0)
and then it should stop doing what its doing.
May look at whats best there at that point, this, a substr or a simple regex, but anyway.