You say you don't want to sue anyone (which is smart), but your old boss doesn't know that, does he? So a stern letter from a lawyer may be enough to make him think twice about his response to the next prospective employer who calls asking about you.

    Another tactic that works: Put your cards on the table.

    "When an interviewer asks you for references, you can say right up front, 'My former boss and I didn't see eye to eye, so if I may, I'd like to give you contact information for three other people who can tell you about my performance, just so you get a balanced picture'," Allison says.

    "That way, even if your old boss is undermining you, the person who calls him for a reference doesn't get an unpleasant surprise -- and you don't appear to be trying to hide something."

    Alerting an interviewer ahead of time that a particular manager might not be your biggest fan is a relatively low-risk way to go, Allison adds, because "almost everyone has reported to someone, sometime in his or her career, where the personal chemistry just wasn't great. If they really want you, they'll hire you anyway."

    Of course, this approach assumes that you do have other erstwhile bosses and colleagues who would be happy to give you a glowing recommendation. Before you give out their contact information, it never hurts to call them and ask if they'd mind talking you up. You can even coach them a little on which aspects of your past performance you'd appreciate their mentioning.

    Luckily, there's a good chance that, with a few friendly ex-coworkers in your corner, you don't need your old boss at all. A few days ago, curious about how crucial a former boss's recommendation really is, I asked executive recruiters Korn Ferry International to conduct an informal online poll of managers visiting the firm's web site.

    The question: "When you are considering hiring someone, is a reference or recommendation from the person's last boss an absolute prerequisite?"

    You may be cheered by the result: Of the 252 managers who answered the question, 89% said "no."

    Talkback: Have you ever worked for someone you would hesitate to give as a reference? Have you ever given a negative reference to someone else? Leave a comment below.