If you shoot an arrow into a portal it will go through not into the nether (normal) but if you then go into the nether you get a item picking up sound even though there is no item and I'm guessing the picking up sound is the ghost arrow which did not go to the nether.
MC-169
Pickup sound after following arrow into a portal
Resolved
Fixed
0
Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.
I tried to reproduce that with 1.4.5 but the arrows go through the portal, please verify.