leveldb-ruby build fail

gistfile1.txt

g++ -I. -I/Users/username/.rvm/rubies/ree-1.8.7-2011.01/lib/ruby/1.8/i686-darwin10.6.0 -I/Users/username/.rvm/rubies/ree-1.8.7-2011.01/lib/ruby/1.8/i686-darwin10.6.0 -I. -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -fno-common -g -O2  -pipe -fno-common  -I../../leveldb/include   -c leveldb.cc
g++ -shared -o leveldb.bundle leveldb.o -L. -L/Users/username/.rvm/rubies/ree-1.8.7-2011.01/lib -L.     -ldl -lobjc   -L../../leveldb -lleveldb
Undefined symbols:
  "_rb_str_new", referenced from:
      db_each(unsigned long)in leveldb.o
      db_each(unsigned long)in leveldb.o
      db_delete(unsigned long, unsigned long)in leveldb.o
      db_get(unsigned long, unsigned long)in leveldb.o
  "_rb_cObject", referenced from:
      _Init_leveldb in leveldb.o
  "_rb_yield", referenced from:
      db_each(unsigned long)in leveldb.o
  "_rb_exc_new2", referenced from:
      db_make(unsigned long, unsigned long, unsigned long, unsigned long)in leveldb.o
      db_each(unsigned long)in leveldb.o
      db_size(unsigned long)in leveldb.o
      db_delete(unsigned long, unsigned long)in leveldb.o
      db_put(unsigned long, unsigned long, unsigned long)in leveldb.o
      db_get(unsigned long, unsigned long)in leveldb.o
  "_rb_ary_push", referenced from:
      db_each(unsigned long)in leveldb.o
      db_each(unsigned long)in leveldb.o
  "_rb_define_module", referenced from:
      _Init_leveldb in leveldb.o
  "_rb_define_singleton_method", referenced from:
      _Init_leveldb in leveldb.o
  "_rb_define_method", referenced from:
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
  "_rb_exc_raise", referenced from:
      db_make(unsigned long, unsigned long, unsigned long, unsigned long)in leveldb.o
      db_each(unsigned long)in leveldb.o
      db_size(unsigned long)in leveldb.o
      db_delete(unsigned long, unsigned long)in leveldb.o
      db_put(unsigned long, unsigned long, unsigned long)in leveldb.o
      db_get(unsigned long, unsigned long)in leveldb.o
  "_rb_ary_new2", referenced from:
      db_each(unsigned long)in leveldb.o
  "_rb_iv_set", referenced from:
      db_init(unsigned long, unsigned long)in leveldb.o
  "_rb_int2inum", referenced from:
      db_size(unsigned long)in leveldb.o
  "_rb_eStandardError", referenced from:
      _Init_leveldb in leveldb.o
  "_rb_check_type", referenced from:
      db_close(unsigned long)in leveldb.o
      db_make(unsigned long, unsigned long, unsigned long, unsigned long)in leveldb.o
      db_each(unsigned long)in leveldb.o
      db_size(unsigned long)in leveldb.o
      db_delete(unsigned long, unsigned long)in leveldb.o
      db_delete(unsigned long, unsigned long)in leveldb.o
      db_exists(unsigned long, unsigned long)in leveldb.o
      db_exists(unsigned long, unsigned long)in leveldb.o
      db_put(unsigned long, unsigned long, unsigned long)in leveldb.o
      db_put(unsigned long, unsigned long, unsigned long)in leveldb.o
      db_put(unsigned long, unsigned long, unsigned long)in leveldb.o
      db_get(unsigned long, unsigned long)in leveldb.o
      db_get(unsigned long, unsigned long)in leveldb.o
  "_rb_define_class_under", referenced from:
      _Init_leveldb in leveldb.o
      _Init_leveldb in leveldb.o
  "_rb_data_object_alloc", referenced from:
      db_make(unsigned long, unsigned long, unsigned long, unsigned long)in leveldb.o
  "_rb_obj_call_init", referenced from:
      db_make(unsigned long, unsigned long, unsigned long, unsigned long)in leveldb.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make: *** [leveldb.bundle] Error 1


Gem files will remain installed in /Users/username/.rvm/gems/ree-1.8.7-2011.01/gems/leveldb-ruby-0.7 for inspection.
Results logged to /Users/username/.rvm/gems/ree-1.8.7-2011.01/gems/leveldb-ruby-0.7/ext/leveldb/gem_make.out