Multiple References on one Foreign Key

I hope this is the right place to ask this question.  I've search the archives
the news groups and could not find anything so I apologize if this has been
answered previously.

Here is my sample table:

CREATE TABLE master2 (
  id int primary key,
  name varchar(32),
  nickname varchar(32),
  unique (name,nickname)
);


This issue is this:

create table reftest2 (
 id int primary key,
 invited varchar(32),
 foreign key (invited) references master2 (name,nickname) on update
cascade on d
elete
 cascade
);


This produces the following message:

"ERROR:  CREATE TABLE: number of referencing and referenced attributes
for
foreign key disagree"

The idea is that I want to have invited in reftest2 be constrainted
against name
and nickname in the master2 table (actually I really don't want to
"unique
(name,nickname)" in master2, I'd rather have name and nickname be
unique within
themselves if possible)


Is this possible?


--
Keith C. Perry
Director of Networks & Applications
VCSN, Inc.
http://vcsn.com

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