Half working trust relationship between Domains

I created a trust relationship between 2 servers w/ server 2003. From server/DC “A” everything works fine, I can directly access a shared folder from computers that belongs to server/DC “B”. But from server/DC B it does access anything from server/DC A. It asks for a domain password and even if I supply a right user/password from the domain, it still say access denied. I undid the trust relationship, which was a bi-directional and was made from server A, an tried to re-do it from server B. In the last stage of the creation, when asked to supply the domain password (in this case a user/password from server “A”) it simple says access denied, as if I was not able to access the AD and validate the password. Any ideas anyone?