CREATE INDEX test_idx ON test (UPPER(varchar_field)) doesn't work...

Hi -Someone on -general suggested I bring this up here.  I'll try and
explain as much as I can.  If you need more information from me, please
let me know.  I think the easiest way to illustrate this is to just paste
in the output.  This is all happening on FreeBSD 3.4 running 7.0.2.

--------------------------------------------------------------------------
devloki=> CREATE TABLE test (field VARCHAR(10));
CREATE
devloki=> \d test                           Table "test"Attribute |    Type     | Modifier 
-----------+-------------+----------field     | varchar(10) | 

devloki=> INSERT INTO test VALUES ('test string');
INSERT 110505 1
devloki=> SELECT field FROM test;  field    
------------test strin
(1 row)

devloki=> SELECT UPPER(field) FROM test;  upper    
------------TEST STRIN
(1 row)

devloki=> CREATE INDEX test_idx ON test (field);
CREATE
devloki=> CREATE INDEX test_upper_idx ON test (UPPER(field));
ERROR:  DefineIndex: function 'upper(varchar)' does not exist
--------------------------------------------------------------------------

Is there any other information I can provide?  Should I send this on to
-bugs?

Thanks,

-philip