A joke

A man named Dodgin was recently appointed foreman at a factory, but his name was not known to all the employees.
One day while on his rounds he came across two men sitting in a corner, smoking, and stopped near them. "Who are you?" said one of the men. “I'm Dodgin, the new foreman," he replied. "So are we," replied the other workers, “sit down and have a smoke."

This is a joke and I don't understand it. Could you tell me what is so funny here?