This looks more like a Rails generator issue,
add_dependency does no require'ing, you have do that
all yourself. I would post this to Rails-talk or hop on
#rubyonrails and see whats up. Sadly I don't know too much about
the generators for Rails, their API is in constant flux and I've
always had issues making them myself :(
A conversation has been started with the RubyGems.org staff to resolve this discussion.