I have wondered the same thing. It appears that
Oman was at least involved, but I can't believe they "donated" out of the goodness of their heart.
Given the comment I heard this morning on my local radio news (which I can't confirm on the Internet) that one of the hitchhikers said the reason they were held was because of the atrocities America committed at Abu Ghraib,
I wouldn't be surprised to find that Code Pink had subsidized the "bail". 