I found this while testing MinecraftForge/MinecraftForge#4680. The PR fixes an inconsistency between vanilla glass and modded glass. This is done by checking if the block face that's against the water block is solid, however Buildcraft pipes always return BlockFaceShape.SOLID even without a facade.

Also tested with the version here on github and the issue changed to some returning BlockFaceShape.UNDEFINED when they shouldn't (i.e. Glass facade), seems to have changed because of the getBlockFaceShape() override on 8aa06a8.

BuildCraft version: 7.99.14
Forge version:
Link to crash report or log:
Singleplayer or multiplayer: Both
Additional information: