Sinwei, one day (2 years ago perhaps) someone that was not Christian, from my town, died. I went to the funeral and tought to myself that dying without a place to go could be hard, so i tried to speak mentally with the deceased.
Of course that i didnt have a mean to know if he could "hear" my toughts, but i give it a try. Then, carefully and without to much words, i told him about Amitabha and the idea behind it. I told him that he could try to reborn there and then i said Namo Amitabha Buddha a few times.
It was not imediatly, but i remember seeing somewhere, during the funeral ceremony, a kind of rainbow in the clouds. Not a typical rainbow but more like this (see the pics in the link):http://www.flickr.com/photos/tkellyphoto/390592135/http://adnams.co.uk/wp-content/uploads/2010/01/ice-rainbow1.jpg
Of course that it could be just a pure coincidence, but we can also think that Amitabha has intervened in such a way that such rainbow could be created by natural phenomenon. The same applys for the rainbow in the retreat.