NO NO NO!! Don't spray with water, this will make it swell, use sugar water. I had this happen to me. At first I panicked, but remember Roy's advice of sugar water, or even pure sugar. The sugar draws out the fluid in the hemipene and helps the snake to withdraw it.
So sugar water, or pure sugar (not salt!!!) and see a vet, ASAP. The hemipene may have to be amputated if he doesn't withdraw it or if it necrotizes. Good luck!
Katt, typing under Vanan's ID.
The Herp Room
"The day I tried to live, I wallowed in the blood and mud with all the other pigs" - C. Cornell