Is it dishonest to use tact when talking to someone?

When I have something important to tell someone and I am concerned that the other person might be put on the defensive or have hurt feelings, I try to say what I need to say with tact. That is, I change what I say from brutal honesty to something a little more tactful. As long as the message is the same and I am being honest, is the use of tact in and of itself necessarily dishonest or wrong?