Here’s a link to the final Communique from the G20 meeting:
Communiqué
Meeting of Finance Ministers and Central Bank Governors
Moscow, 15-16 February 2013 (PDF)
Also here: Сommunique of Finance Ministers and Central Bank Governors, Moscow
For a summary, here’s Reuters with the key passages: TEXT-Main points of final G20 finance communique
As expected, there is no specific mention of Japan or Japanese policy. In brief, if policy is aimed at achieving results in the domestic economy then its OK. Of course, it is difficult to gauge whether domestic policies are, or are not, aimed at weakening the currency.