Unpack Gems equivalent in Rails 3

I usually use rake gems:unpack to gain access to the source of my gems
while developing. I find it to be a very easy way to dig into what a gem
expects or to see how it works inside. I was trying out Hobo edge on
Rails 3, and hit a bug I wanted to fix, but couldn’t find an equivalent
way to get the source of that gem. StackOverflow kindly offered up
bundle package as the equivalent of gems:unpack, but that gets me
compiled versions, not the source. I can see how package would be useful
for the “real” purpose of unpack – portable gems for deployment. But
that utterly fails for what I’m trying to do here. Any ideas?

Thanks in advance,

Walter