query failed , don't know why

UPDATE members m,payments p SET m.status = 2 WHERE p.paydate > 'now'::datetime - '1 month'::timespan and p.productid =
'xxxxxxx'and m.gid = p.gid
 

i'm trying to run that query and i'm getting 

"parse error near m"

but it looks ok to me 

i'm running postgresql 7.0.2 with freebsd 4.0 stable

jeff