Old phones weren't really resistant; but less sensitive. My Samsung Wave 723 took a plunge once, water got inside but almost didn't harm it (almost; something SMTc wasn't properly functioning after 1h of use). Kinda like ThinkPads, they can leak water outside a bit, but they're not water tight sealed.
I was about to say the board was probably empty, but turns out it's not that simple http://3.bp.blogspot.com/-shGknjKjPWE/TzJGOwQLVcI/AAAAAAAAAE...
Old phones weren't really resistant; but less sensitive. My Samsung Wave 723 took a plunge once, water got inside but almost didn't harm it (almost; something SMTc wasn't properly functioning after 1h of use). Kinda like ThinkPads, they can leak water outside a bit, but they're not water tight sealed.