error message

hi, i'm using access97 linked to postgres(6.4.2) tables through the new 
v.6.4 odbc.  i can open a form, it shows me data for an initial record, and 
then bombs.  here is the message in the log file -- i can't figure out why 
it is bombing.  does anyone have a clue??  do those "-" or "/" in various 
"vinvnum" fields cause problems??  it shows valid data first, waits for a 
second, and then bombs!

TIA, jt

conn=50745568, query='declare SQL_CUR0308FC60 cursor for SELECT 
"vnum","vinvnum","vinvrecdt","vinvduedt","vinvamt","glnum","checkdt","ch  
ecknum","ponum",'#S_C_H#'  FROM "ap"  WHERE "vnum" = 20000 AND "vinvnum" = 
'13639 VOID' OR "vnum" = 20000 AND "vinvnum" = '138577-Void' OR "vnum" = 
20000 AND "vinvnum" = '142185-SHOP' OR "vnum" = 20000 AND "vinvnum" = 
'2Brother Credit 1/99' OR "vnum" = 20000 AND "vinvnum" = '37003 OFO-Chairs' 
OR "vnum" = 20000 AND "vinvnum" = 'Aberdene, SD' OR "vnum" = 20000 AND 
"vinvnum" = 'Adj for Nov' OR "vnum" = 20000 AND "vinvnum" = 'Adj for Oct 
97' OR "vnum" = 20000 AND "vinvnum" = 'Agson 132289' OR "vnum" = 20000 AND 
"vinvnum" = 'Air Trans''
ERROR from backend during send_query: 'ERROR:  Unable to find an ordering 
operator '<' for type unknown.Use an explicit ordering operator or modify the query.'
conn=50745568, query='ABORT'
STATEMENT ERROR: func=SC_execute, desc='', errnum=1, errmsg='Error while 
executing the query'               --------------------------------------------------------  
----                hdbc=50745568, stmt=50920544, result=0                manual_result=0, prepare=1, internal=0
       bindings=0, bindings_allocated=0                parameters=50911028, parameters_allocated=20
statement_type=0,statement='SELECT 
 
"vnum","vinvnum","vinvrecdt","vinvduedt","vinvamt","glnum","checkdt","ch  
ecknum","ponum",'#S_C_H#'  FROM "ap"  WHERE "vnum" = ? AND "vinvnum" = ? OR 
"vnum" = ? AND "vinvnum" = ? OR "vnum" = ? AND "vinvnum" = ? OR "vnum" = ? 
AND "vinvnum" = ? OR "vnum" = ? AND "vinvnum" = ? OR "vnum" = ? AND 
"vinvnum" = ? OR "vnum" = ? AND "vinvnum" = ? OR "vnum" = ? AND "vinvnum" = 
? OR "vnum" = ? AND "vinvnum" = ? OR "vnum" = ? AND "vinvnum" = ?'                stmt_with_params='declare
SQL_CUR0308FC60cursor for 
 
SELECT 
"vnum","vinvnum","vinvrecdt","vinvduedt","vinvamt","glnum","checkdt","ch  
ecknum","ponum",'#S_C_H#'  FROM "ap"  WHERE "vnum" = 20000 AND "vinvnum" = 
'13639 VOID' OR "vnum" = 20000 AND "vinvnum" = '138577-Void' OR "vnum" = 
20000 AND "vinvnum" = '142185-SHOP' OR "vnum" = 20000 AND "vinvnum" = 
'2Brother Credit 1/99' OR "vnum" = 20000 AND "vinvnum" = '37003 OFO-Chairs' 
OR "vnum" = 20000 AND "vinvnum" = 'Aberdene, SD' OR "vnum" = 20000 AND 
"vinvnum" = 'Adj for Nov' OR "vnum" = 20000 AND "vinvnum" = 'Adj for Oct 
97' OR "vnum" = 20000 AND "vinvnum" = 'Agson 132289' OR "vnum" = 20000 AND 
"vinvnum" = 'Air Trans''                data_at_exec=-1, current_exec_param=-1, put_data=0                currTuple=-1,
current_col=-1,lobj_fd=-1                maxRows=0, rowset_size=1, keyset_size=0, cursor_type=0, 
 
scroll_concurrency=1                cursor_name='SQL_CUR0308FC60'                ----------------QResult Info 
-------------------------------
CONN ERROR: func=SC_execute, desc='', errnum=110, errmsg='ERROR:  Unable to 
find an ordering operator '<' for type unknown.Use an explicit ordering operator or modify the query.'
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