'=' character removed from request cookie

I'm saving encrypted user token in session cookie:
Cookie: JCORESESSIONID=aes256$/tew4VVsfdJ32iUX1AOqBGRb717TJC9KkejjAPl6BIAG6kCP4beSraL51eQG2iu5bV9uT3OsubXUcjO+sG2lYNWbu5NliQd361oUz2Yl4LQ=

The problem is that in the server i see that the '=' character is removed hence i cannot decrypt it.