It rained this morning. As usual I took my North Face ripstop nylon shell and put it over my puff jacket (it was barely above freezing). However, when I took the shell off, I noticed my puff jacket was wet. Now, I highly doubt that water came in through the neck hole of my shell and got the outside of my puff jacket wet (especially along the arms) so the only conclusion I can make is that my shell is no longer waterproof.

As far as I know, ripstop nylon doesn't require any tech spray to keep it waterproof.

So my question is this. Are there any thin, lightweight shells what are ACTUALLY waterproof, forever? (My pants/trousers faired better, but they're also quite a bit thicker (and heavier.))