I've ruined just about every pair of boardshorts I own by putting them through the wash with wax in the pockets. Im my experience it completely melts the wax.
lol i broke my moms dryer with a brand new stick of wax, the dryer was old so it was time for her to upgrade anyways lol. several of my board shorts also have the wax caked into the pocket, but it was just that one time that it made it out of the pocket. i say if its still intact, give it a try, the worse that could happen is you having to take it off