Dear Lazyweb: Proc disassembly in 1.9?

Clue me? How do I disassemble a proc in 1.9?

>> p = proc { |n| n + 2 } 
=> #<Proc:0x3be994@(irb):1>
>> VM::InstructionSequence.disassemble p
>> class Temp1; end
>> Temp1.send :define_method, :m, p
=> #<Proc:0x3be9e4@(irb):1 (lambda)>
>> VM::InstructionSequence.disassemble(Temp1.instance_method :m)
=> nil
>> VM::InstructionSequence.disassemble(Temp1.new.method(:m))
=> nil
>> class Temp2; def m; 1 + 2; end; end
=> nil
>> puts VM::InstructionSequence.disassemble(Temp2.instance_method(:m))
== disasm: <ISeq:x@(irb)>===============================================
0000 putobject        1                                               (  12)
0002 putobject        2
0004 opt_plus         
0005 leave            
=> nil