Not to mimic the 1 Corinthians guy, but what justification is there for female preachers in Christianity?

Mary Magdalene was one of Jesus' disciples. When Martha scolded her for learning at Jesus' feet rather than helping in the kitchen, Jesus said she had just as much right as a man to learn what he taught. Women were the first to see the empty tomb and the first to see the risen Christ. If women were disciples, why shouldn't they be preachers? Paul was writing from the preconceptions of the time, which Jesus was attempting to change.