i am using WS-G5487 (1000BASE-ZX) on couple of my optical links and they are working just fine. but next week i have to establish two link that are over 70 KM (77 and 78 KM). in WS-G5487 data sheet max range on G.652 is about 70 KM. so if someone has had any experience with WS-G5487 on optical spans over 70 KM please reply. i am afraid that this is not going to work and if i have to make up some different solution probably it will be more expensive. thanks in advance.