Rake error

wingrunr21@wings ~/Desktop/rubinius > ./configure
Configuring LLVM...
  Checking for existing LLVM tree: found!

Checking sizeof(long): 8 bytes
Checking platform endianness: little endian
Checking tr1/hash definition: found
Checking for function 'backtrace': found!
Checking for function 'readline': found!
Checking curses library: curses

Configured. Run 'rake' to build and run VM tests and rubyspecs.

After building, you may add '/Users/wingrunr21/Desktop/rubinius/bin' to your PATH or run commands directly from that directory. Available commands are:

  rbx, ruby, rake, gem, irb, rdoc, ri

wingrunr21@wings ~/Desktop/rubinius > rake
(in /Users/wingrunr21/Desktop/rubinius)

Unable to build using the running Ruby executable.

To resolve this issue:
  * Use '/Users/wingrunr21/.rvm/rubies/ruby-1.8.7-p302/bin/ruby' to build.
wingrunr21@wings ~/Desktop/rubinius > ruby -v
ruby 1.8.7 (2010-08-16 patchlevel 302) [i686-darwin10.4.0]