Pack it with O2 grease. I found that grease keeps everything uncorroded and also gives the water nowhere to go.
For what it's worth, I think the pic Stephane posted is excellent and a mod all users should make. If you want to see what happens to a VR£ cable unsealed then look
here.
Monkey, do check the cabling if you're getting dodgy readings because that's exactly what the symptoms were for my cable. Don't forget that corrosion can creep up from the molex end (just like on an Inspo) because of the crimp exposing the inner conductor. It's a crap connection method. If I were to go back to using VR£ for 4th cell, I'd undo the gland, drill out the potting and replace it with a sealed SMB connector.
HTH