Have scientists drilled into Lake Vostok?

Lake Vostok is a very large lake underneath the main 2km-thick ice sheet of eastern Antarctica and has been isolated from surface for a half a million years. There has been a project to drill through the ice sheet down to Lake Vostok that's been running for quite a few years. They started drilling and got to about 50 metres above the lake itself and decided to stop. They weren't sure if there would be any life in the lake, and there was also the problem of infecting the lake with modern microbial material. It could therefore contaminate an undisturbed environment. People have been trying to invent a sterile drill to get around these problems. I don't know the exact date of going into the Lake.