Oil level sending unit leaks?

I have a '99 Montan and it appears that I have a small leak around the oil level sending unit in the bottom of the oil pan. It appears to only do this when it is cold. I noticed it a little last winter, went away in the summer and now that it has cooled off again, a few drips under the van each morning. Anyone else experience this? There is no apparent leaking running down the pan to this unit, just a little collects right around the wires and underneath it. Next time I change the oil I'm pulling the unit out and putting some gasket sealer around where it seals against the oil pan and reinstalling but just wondering if anyone else has expreienced this.