This was published back in February of 2006 at the Space Technology
and Applications International Forum (STAIF)

This is an online press release by NASA about the paper dated February
10, 2006.
http://www.nasaspaceflight.com/2006/02/felber-to-present-near-light-speed-concep\
t/

This is the actual paper that was published.
http://arxiv.org/vc/gr-qc/papers/0505/0505099v1.pdf

I am still trying to understand all the implications if this effect
can be verified.