Ben Watson
Comments
Confirmed in 1.8.1-pre5
I tested this with the Minecraft Launcher, with Pre-release 1, 2 and 3 and got excatly the same result.
I know this may not really mean anything, but I was using Magic Launcher (with no mods loaded) instead of the Minecraft Launcher.
To support /u/redstonehelper, Hypixel is modded and here's why:
For something to not be modded, it has to be a "Vanilla Minecraft Server" downloaded directly from the Mojang Website. Hypixel uses BungeeCord, which is a mod of the original Vanilla Minecraft Server files. They use Bukkit plugins which count as mods. They also allow 1.7.2-1.8.8 clients to join, while Vanilla Minecraft Servers do not allow this.
Even though you may not be using Forge Mod Loader/Liteloader when you join, the server is using a plugin loader named Spigot/BungeeCord to load their own custom mods.
I believe that the main reason that Hypixel doesn't register your hits is because 1.7 and 1.8 pvp are slightly different and Hypixel caters to 1.7's PVP style because Spigot 1.7-1.8 protocol hack is built upon 1.7.10.