South Korea upgrading communications with North Korea

I just saw this headline this afternoon; though it was two days old, it was the first I had heard of it. While I suppose a communication infrastructure between the two Koreas is convenient, it hardly seems necessary. Particularly in light of the fact that one of the communication hotlines runs to an unused resort in the North, owned by a South Korean company. The article also snuck in, near the bottom of the page, the revelation that "the rival militaries also share a hotline." Does this seem strange to anyone, for two nations that have technically been 'at war' for the last 50-odd years to be sharing military information?