Accord V6 tansmission leak

Wife has a 2000 Honda Accord VX V6 noticed a spot of oil the other day on the garage floor.After looking under car its transmission fluid.It is on the passenger side its coming from a looks like metal cover that goes on the bottom of the transmission.Checked all the bolts and they are tight.What is under the cover?Shop manual I have(Clymer) does not show anything about this.Guess I will have to get me a Honda shop manual to see what is under there.It is just a seep now.Level was full but after looking under there was a drop ready to drip do the floor.Anybody have any idead what this is or what is under there?