Problem with the login from internet explorer

I first at all congratulations for the theme

i have build a social network,and everything works ok, except when you tried to login from internet explorer, that returns a 400 error, but if you refresh you can access the social network and you are already logged.

I sure that it’s a line of code, write in the right place. How you have build sure that you can solve the problem.

Pleased some help, the client is so heavy and i am desperate, i have tried everything.

to logging in to the social network you can use this

user : luisen

password: 85588558

The page is http://salmon-ized.com/

You can see as well in the proof domain

s615087721.mialojamiento.es/#

Both have exactly the same code