downgrade from WM 6.5

[Guest bundy67]

I recently flash my i780 to customised WM 6.5 from WM 6.1. Now i regret it and trying to look for WM 6.1 ROM image to downgrade it. Any one can assist to post me a link for the WM 6.1. I am unable to use the official one from Samsung, as the WM 6.5 keep having problem with the active sync

Thanks for any help provided