Table design; 2-column index

[Wellington Fan]

Hello List,

If I have a table:

CREATE TABLE t (
  id int(11) NOT NULL auto_increment,
  fk1 mediumint(9) NOT NULL default '0',
  fk2 smallint(6) NOT NULL default '0',
  PRIMARY KEY  (id),
  UNIQUE KEY idxfk1 (fk1,fk2),
  UNIQUE KEY idxfk2 (fk2,fk1)
) TYPE=MyISAM;

I will about half the time have a query "WHERE fk1 IN (....)" and about the other half the
time have "WHERE fk2 IN (....)"

Does it make sense to define the UNIQUE KEYS the way I have?

Thanks!

--
Wellington