Serving Sara (2002)
Serving Sara is a 2002 romantic comedy film which stars Matthew Perry, Elizabeth Hurley, and Bruce Campbell. Joe Tyler (Perry) is a process server who is given the assignment to serve Sara Moore (Hurley) with divorce papers. He does so, but Moore persuades Tyler to serve Moore's husband instead so that she can get a larger portion of his money in the divorce. The rest of the film follows their attempt to carry out Sara's plan.
More at Wikipedia.