Uh, don't think that I'm crazy... But I suggest that your wash it with water before you soak it into rice(hopefully again). Sea water is salty you see, and salt isn't what I would bear to have in electronical gadgets. It messes it up somehow. Not that sure about this though
Perfect advice. Salt water will destroy circuit boards, and if it is concentrated by evaporating the water it will be even more destructive. With the history of this phone I'm estimating less than 5% chance it will ever work again. For all practical considerations the phone is toast.
My advice is to remove the battery now, and not put it back until the phone is washed out to remove all salt, AND completely dried. The phone needs at least 3 soaks in DISTILLED water (deionized is also ok and might be easier to find). Flood the phone completely (it's already wet and salty, it can't get worse) for a few minutes, then drain the phone for about 5 minutes on an adsorbent cloth. Pour away the water and replace with fresh, repeat at least 3 more times and drain as much as possible.
Now you have two choices to dry the phone - and that also means ALL the water trapped under the chips, etc on the pcb, not just a quick wipe and shake. Forget about rice, it is fine as emergency first aid if it is all you have, but not up to the same standard of drying as you get from silica gel. My suggestion is to put the phone in a sealed box with at least 8 ounces of freshly dried silica gel, and leave it for at least a week. It should be easy to find silica gel online (ebay?) and it can be dried and re-activated by heating for a few hours at about 120C in a regular oven (not a microwave).
The other method used during manufacture is to clear the water by rinsing in isopropanol to remove the moisture. However this really needs the phone to be opened up so you can treat only the PCBs (not the case) and be sure any isopropanol vapor has been cleared before you power up.