The following bug has been logged online:

Bug reference: 1966
Logged by: Tony Caduto
Email address: tony_caduto (AT) amsoftwaredesign (DOT) com
PostgreSQL version: 8.1
Operating system: Linux
Description: Single OUT PARM does not return param name.
Details:

When creating a plpgsql function that has one OUT param the function returns
the name of the function as the column name instead of the OUT param name.
This behavior is not consistant with the behavior of other DB systems and
needs to be fixed so that if a single OUT param is specifed the name of the
param is returned.

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Tony Caduto wrote:
This will be fixed in 8.1beta3. Thanks for the report.

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