There was too much voodoo going on in new_sid(). Just use uniqid() with
a random seed and the optional entropy parameter to generate MD5 input.

Use the remote IP address as a salt to reduce the chance of two clients
getting the same ID if they login at exactly the same time.

Thanks-to: Florian Pritz <bluewind@xinu.at>
Signed-off-by: Lukas Fleischer <archlinux@cryptocrack.de>