[MC-74876] Skin Load Error when 0<Alpha<255

no word ,see the photo
when alpha≠0 , alpha well to 255......
were debug in Server-Mineplex............

Environment

Win7 x64
Java 7 with javac
MCLauncherBN by zhh0000zhh 3.4 from mcbbs.net
OpenGL FX 1700
no mod

This ticket is invalid as it relates to a modified or 3rd party client, server, or launcher.

Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.
Any plugin issues need to be addressed to the creator of the plugin or resource pack.
This site is for addressing issues related to the base unmodded Minecraft; Bukkit, Forge, Optifine, or any other modded system invalidates your ticket, unless it can be shown to happen in Vanilla.
Additionally, if you have problems on large-scale modded servers, please report it to their site. It's probably not a bug in Vanilla Minecraft.

Then either duplicat of MC-56827 or MC-46772

English is not my main language so pardon me for my vocabulary......