It's possible that some of you have seen a shiny green arrow in your Technic Launcher near the Tekkit modpack. Your launcher might even be set to use the 'Latest Version' of the modpack.
Do not update the Tekkit modpack
Updating to 1.2.10cx will prevent you from accessing the server. Once installed, you will not be able to connect even after selecting the server version (1.2.9g) in your launcher.
If you have updated to 1.2.10cx, please reinstall the modpack and make sure that your launcher is set to only use the 'Recommended Version'
CaptainSkies Edit: We have not updated to the "Latest" pack because it is unstable. Majority of servers including Sky Servers Tekkit will remain on the "Recommended" Version.