4GL error -408

Hello all, A simple SELECT (actually, a UNION of 2 SELECTs) produces this error: SQL statement error number -408. Invalid message type received from the sqlexec process. I4GL version is 4.13 UD1 with an SE engine under HP-UX 09.04 on a 9000 box. The SELECT statement in question has an ORDER BY clause with 4 columns listed, one of which is a CHAR(30). We attempted the following: Step 1: SELECT ... UNION SELECT ... INTO TEMP tmp_table WITH NO LOG Step 2: DECLARE cur1 CURSOR FOR SELECT * FROM tmp_table ORDER BY col1, col2, col3, col4 Step 3: FOREACH cur1 INTO ... (and so on...) Still, the error occured. There are only 15(!) rows in tmp_table. The next thing we did was: Step 1a: CREATE INDEX idx_tmp_table ON tmp_table (col1, col2, col3, col4) Sure enough, that didn't help. Informix tech support suggested that the problem is caused by ORDER BY, but offered no solution other than an upgrade which *may* include a fix. The only way to get it to work is to remove all but the first column from ORDER BY. I wonder if anyone has experienced this weird error or knows a solution or a workaround. Thanks In Advance! Eliott.