Hi. I'm running Forge 1.0.6, Buildcraft 2.1.1 and IC2 .90.
Specifically, when I place buildcraft pipes and attempt to use the diamond mining drill to remove the pipe it goes slower than it should and yields no pipe (like I was using my hands). However if I use a bronze pickaxe (IC2 specific) the destruction goes as quick as you'd expect and yields a pipe back.
Since this functionality was there in IC1 and the bronze pickaxe works correctly I have to assume that it's a property of the diamond mining drill.
EDIT
Just wanted to ad that this caries over to machines as well, not only pipes.
Another edit but someone had already posted this as a bug to which the response was
"Not much of a bug. Of course other mods will not recognise this mod's tools as valid tools. Nothing can be done about that." by Alblaka.
If that is the case then why did the mining drill get reconized as a pickaxe in IC1, and why does the bronze pickaxe (also a completely new tool) also get recognized as a pickaxe by mods? I'm wondering if it's a baseclass modification change and the switch to Forge has something to do with it, but again it must be possible to get it reconized simply because the bronze pickaxe yeilds pickaxe results in mods.