Need to adjust rating algorithm to prevent massive 9 vote spikes

I have noticed that some movies with high ratings are because there a huge number of 9 votes ... way out of proportion to the number of 10 votes or 8 votes (as many as 98% of all votes). I know that the IMDB algorithm for determining averages compensates for large numbers of 10 votes or 1 votes, but I think the algorithm should be adjusted to prevent filmmakers from gaming the rating this way as well. This technique appears to be most often used for movies with around 1,000 to 2,500 total votes, although I'm sure IMDB can determine the exact range to check.