Using vars in condition test?

Is is possible to use variables in the condition line like


    # Assign variable

    LISTNAME=procmail

    ...
    ...

    :0
    * ^To:.*$LISTNAME
    procmail-folder

How do I make procmail expand $LISTNAME before sending the test to egrep?

Thanks,

Bill Moseley
moseley(_at_)netcom(_dot_)com