Just yesterday we discussed this issue at my local board, as there is a colleague who has this firm. Wouldn't it be better to ask themmos directly to avoid any last minute surprises? I think that would'nt hurt anyone but on the contrary, the possibility of theymos appearing in the near future saying that it does not allow jambler.io to advertise or sponsor would.
Take a look here.
If you look at the Bitcointalk Community Awards, which will be open for the next 60 days from December 1, the main sponsor is Jambler. In that case, I think the OP should also have coordinated and asked the admin for permission. And I think he already did.