$ ruby -v
ruby 1.8.4 (2005-12-24) [powerpc-darwin8.3.0]

# Example to illustrate the problem
def foo1
   p (1..10).method(:each)
end

def foo2()
   p((1..10).method(:each))
end

def foo3()
   p (1..10).method(:each)
end

foo1 # -> No error
foo2 # -> No error
foo3 # -> Error

__END__

-- Daniel