First of all, I'm still using the old recent launcher for MC 1.4.7 & 1.5.2 and I'm getting Can't connect to minecraft.net. I tested with the uptodate launcher and it works. I guess mojang killed legacy login in their older launchers..
This is a vanilla launcher. I don't know if its temporary or permanent. It breaks older launchers to everyone (Custom ones!)
Duplicate of MCL-1871.
You're not only using the old launcher, you're using an old version of the old launcher.