Unable to authenticate account with minecraft.net - Proxy

[Meister_Li]

Launcher Version: 1.0.1.3

Operating System: Windows 7 64 Bit

Java Version: 1.7.0_04

Antivirus Program: I am using a Proxy to start the Technic Launcher, as I am trying to play at my workplace (in break, of course). It does work quite good with Minecraft, but the Technic Launcher shows the above Message. I am also able to see the Images on the sides in the Launcher when I launch it with the proxy-command, which doesn't happen normally.

Is there any other way to authenticate with Minecraft.net to be able to play Minecraft?

The Command I use is this (Company name removed):

mkdir %appdata%\.techniclauncher\rtemp

java -Dhttp.proxyHost=<Proxy name of my company> -Dhttp.proxyPort=8080 -Xmx800m -jar technic-launcher-latest.jar

Description of Problem:

I am using a Proxy to start the Technic Launcher, as I am trying to play at my workplace (in break, of course). It does work quite good with Minecraft, but the Technic Launcher shows the above Message. I am also able to see the Images on the sides in the Launcher when I launch it with the proxy-command, which doesn't happen normally.

Is there any other way to authenticate with Minecraft.net to be able to play Minecraft?

The Command I use is this (Company name removed):

mkdir %appdata%\.techniclauncher\rtemp

java -Dhttp.proxyHost=<Proxy name of my company> -Dhttp.proxyPort=8080 -Xmx800m -jar technic-launcher-latest.jar

Error Messages:

Unable to authenticate account with minecraft.net

Error Log: