MySQL client programs prompt for a password when invoked with
          a --password or
          -p option that has no following password
          value:
        
$> mysql -u user_name -p
Enter password:
          On some systems, you may find that your password works when
          specified in an option file or on the command line, but not
          when you enter it interactively at the Enter
          password: prompt. This occurs when the library
          provided by the system to read passwords limits password
          values to a small number of characters (typically eight). That
          is a problem with the system library, not with MySQL. To work
          around it, change your MySQL password to a value that is eight
          or fewer characters long, or put your password in an option
          file.