cursor "curs" already in use ?

2 function returns refcursor:

CREATE OR REPLACE FUNCTION per_getjobmind(puid bigint)
  RETURNS refcursor AS
$BODY$
declare
    curs cursor for    select workname,workold    from per_jobmind where
uid=puid;
begin
    open curs;
    return curs;
end;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;

CREATE OR REPLACE FUNCTION per_getjobmind_jobtype(puid bigint)
  RETURNS refcursor AS
$BODY$
declare
    curs cursor for    select jobtypeid from per_jobmind_jobtype where
uid=puid;
begin
    open curs;
    return curs;
end;
$BODY$
LANGUAGE 'plpgsql' VOLATILE;

-------------------------------------------------------------------
java code:

conn.setAutoCommit(false);
cmd = conn.prepareCall("{?=call per_getjobmind(?)}");
cmd.registerOutParameter(1, Types.OTHER);
cmd.setLong(2, uid);
cmd.execute();
rs = (ResultSet) cmd.getObject(1);
if (rs.next()) {//just 1 line
    workname = rs.getString("workname");
    workold = rs.getInt("workold");

}
rs.close();
cmd.close();

cmd = conn.prepareCall("{?=call per_getjobmind_jobtype(?)}");
cmd.registerOutParameter(1, Types.OTHER);
cmd.setLong(2, uid);
cmd.execute();////////////////////////////////// error here," cursor
"curs" already in use"
rs = (ResultSet) cmd.getObject(1);
while (rs.next()) {
    jobtypeid=rs.getInt("jobtypeid");
}
rs.close();
cmd.close();
-----------------------------------------------------------------------
Can I named a refcursor in JDBC? How?