security update gone terribly wrong

okay so i thought my jag was crappy for years but the truth is i was pretty much just abandoned. the last security update for this version of mac (the one on the apple site) doesn't do a thing. it's supposed to install the libpng library or whatever it is but it just doesnt. i searched the whole computer for libpng and didnt find it, tried programs that are supposed to run fine after i install it, like i said bupkiss. anyway somebody's gotta kno what i'm talkin about

what the libpng is supposed to do is make applications using .png files run without crashing (or just run in the first place)

oh yea, i forgot to say its security update 2004-08-09