BUG #3387: mod on non-integer returns bad result

The following bug has been logged online:

Bug reference:      3387
Logged by:          Filip Krska
Email address:      filip.krska@comstar.cz
PostgreSQL version: 8.1.5
Operating system:   CentOS Linux 3.8 on x86_64
Description:        mod on non-integer returns bad result
Details:

Hello,

select mod (70.0,70) from dual;

returns

70.0

instead of

0.0

This happens on x86_64 architecture (e.g. Intel Xeon            E5310, Xeon
DP 3GHz, but not only) with PostgreSQL compiled for x86_64. If compiled for
i686, gives right results.

Bad results occurs for 70.0 and multiples.
e. g.
select mod (60.0,60) from dual;
returns 0.0

Also
select mod (70,70) from dual;
gives 0 correctly.

Thanks, Filip