The deceased is then taken to the cemetery for burial (al-dafin). While all members of the community attend the funeral prayers, only the men of the community accompany the body to the gravesite. It is preferred for a Muslim to be buried where he or she died, and not be transported to another location or country (which may cause delays or require embalming the body). If available, a cemetery (or section of one) set aside for Muslims is preferred. The deceased is laid in the grave (without a coffin if permitted by local law) on his or her right side, facing Mecca. At the gravesite, it is discouraged for people to erect tombstones, elaborate markers, or put flowers or other momentos. Rather, one should humbly remember Allah and His mercy, and pray for the deceased.
http://islam.about.com/cs/elderly/a/funerals.htm
I’m sure there is an elaborate tape by Usama telling us what to do with his body. Burial at sea is not part of it.