Is the EC-20 2.0x Teleconverter Weather Resistant ?

I think I've read somewhere that the EC-20 2.0x Teleconverter is Weather Resistant as the EC-14 1.4x Teleconverter, is that right ?, also does the AF works with the:

12-60 + EC-20 and 12-60 + EC-1.4 ?
50-200 + EC-20 and 50-200 + EC-1.4 ?

I think I've read somewhere that AF does not work with all the lenses, is some cases only MF will work, any previous experience ?, thanks