Drinking water from the backpack hose will cause client to disconnect, no logs printed that I was able to locate.

Forge v 10.13.4.1614-1.7.10
AB2 v 1.7.10-0.8c

Is it possible that this is deprecated?

I'm seeing this same issue using Forge 1558.

The following was in the server log - http://pastebin.com/48kK40SV

It happens with melon juice as well (it was apparently the drink action, not the fluid). The server reports the same nosuchfielderror:field_70118_ct that rckymtnrfc mentioned. If fastcraft is enabled, it reports as being due to fastcraft (this is not a problem with fastcraft though as it crashes with fastcraft turned off as well). Hopefully this project is picked back up, because it has the potential to be my new favorite backpack mod.