Usage of RETURN QUERY

Hello,

I'm trying to use RETURN QUERY in a function (see query below) in order to
return list of issues and number of times when each issue occurred.

When I try to run the query, it outputs:

ERROR: syntax error at or near "RETURN"
LINE 5: RETURN QUERY SELECT COUNT(tbl_rpc_data.data) AS count, tbl_r...
^
********** Error **********

ERROR: syntax error at or near "RETURN"
SQL state: 42601

I also tried running RETURN QUERY EXECUTE '...' USING ... -- the same
result.

I'm using 'PostgreSQL 9.0.1, compiled by Visual C++ build 1500, 64-bit ' on
64-bit Windows 7 Ultimate.

The text of the query:

--DROP FUNCTION dbglogs_golden.get_grouped_issues_by_agents(integer[]);

CREATE OR REPLACE FUNCTION
dbglogs_golden.get_grouped_issues_by_agents(_p_agent_ids integer[])
RETURNS TABLE(_count integer, _desc text) AS $$

RETURN QUERY SELECT COUNT(tbl_rpc_data.data) AS count, tbl_rpc_data.data
FROM dbglogs_golden.tbl_rpc_messages, dbglogs_debug.tbl_severity_levels,
dbglogs_golden.tbl_rpc_data, dbglogs_product_agent.tbl_product_agents
WHERE tbl_severity_levels.severity_level_id =
tbl_rpc_messages.severity_level_id AND
tbl_rpc_data.data_id = tbl_rpc_messages.data_id AND
tbl_product_agents.product_agent_id =
tbl_rpc_messages.product_agent_id AND
tbl_rpc_messages.product_agent_id = ANY(_p_agent_ids) AND
tbl_severity_levels.severity_level_id IN (1, 2, 4, 5)
GROUP BY tbl_rpc_data.data
ORDER BY count DESC;

END;

$$ LANGUAGE 'plpgsql';
ALTER FUNCTION dbglogs_golden.get_grouped_issues_by_agents(integer[]) OWNER
TO ed;