there seems to be alot of similar thread around. you can do a search in this forum to get all the info you need bout this.
for me, my girl have not sleep through the night but then she only wakes up at 5.30am (after sun rise here in japan) for her 1st milk then sleep again till 7.30am rise n shine.. what i did was jsut stop giving her milk when she wakes up before sun rise. instead, i pat her n reassure her with my voice asking her to go back to sleep etc etc. if she keeps crying i will put her between me n hubby. this usually works cos im rather sure she isnt hungry in midnight. she fell asleep immediately after being placed between me n hubby.. recently i started to 'somehow' co sleep with her n she have not been waking up midnight at all so far. just woke up around 5am for milk then go back to sleep again. the best part is i dont even need to wake up or move! cos she will crawl to me n then pull down my top (im wearing spaghetti strap top) n then latch on herself. after that she will crawl back to sleep