Musannaf Ibn Abi Shayba 35:429

Yazid ibn Harun narrated to us, Muhammad ibn Ishaq narrated to us, from Sa'id ibn al-Sabbaq, from his father, from Sahl ibn Hunayf, who said: I used to experience severe difficulty from madhy (prostatic fluid), and I used to perform ghusl (full ablution) frequently because of it. I mentioned that to the Messenger of Allah (peace and blessings of Allah be upon him), and he said: "It is sufficient for you in that regard to perform wudu (ablution)." I said: "O Messenger of Allah, what about what gets on my garment?" He said: "It is sufficient for you to take a handful of water and sprinkle it over your garment where you see that it has reached."