I remember just some of the scenes... this sci-fi movie was about a crew that lands on a planet, the ship has no fuel and the crew tries to get some energy... by doing sex for example. With the alien women.. other scene was how a man of the crew was chased by a big penis.. the crew-man jumps in a hole and the penis get stuck... the movie was also very funny :)

Sounds like a scene from Flesh Gordon.