Ah. Perhaps we should ask the perl maintainers to add a --teddy-bear option to perl -d:

$ perl -d --teddy-bear buggy.pl

Loading DB routines from perl5db.pl version 1.4
Loading teddy-bear routines from perl5teddy.pl version 1.1
Editor support available.
Plush cuddly support available.

[Teddy: waits attentively]
  Tb<1> I'm not getting all the keys of my hash printed.
[Teddy: waits attentively]
  Tb<2>
...
[download]

Or would users prefer an --eliza mode?

Eliza: Hello. I am ELIZA. How can I help you?
  El<1> I'm not getting all the keys of my hash printed.
Eliza: Why do you say your hash printed? 
  El<2> What?  Wait, it didn't.
Eliza: Does that question interest you?
  El<3> No.  My hash keys interest me.  They're missing.
Eliza: Why do you say your hash keys interest you theyre missing? 
  El<4> ^C^C^C
[download]

On second thought, maybe the teddy bear idea was better.