same problem here but i think i have now cured at little cost, garage repair quote was obscene.
bought a good quality household exterior clear sealant, around sunroof outer side put masking tape on car roof leaving a 2mm gap and go all the way around sunroof with sealant use finger to get perfect finish and remove tape also open sun roof and dry off water on rubber seal, i removed the rubber seal and put sealant all the way around and replaced the old rubber seal, then remove aeriel via interior light the plastic bits will pop out and after removing the bolt for the aeriel put a little sealant on the plastic and refit i also put a little glue around the plastic on outside after fitting but the only problem is you can't adjust aeriel as you will break seal but worth it as you won't need the brolly!!!!! last thing you will need a few dry days to give seal time to dry. good luck
mosti, swansea jack, October 2007