First I've heard of it, and although Hendrix did spend a lot of time in the studio, both straight and stoned, there are lots of people out there always trying to get one more buck out of him.
He did play bass on some material and it's possible that someone got some of the thousands of hours of tapes that he did and is trying to put out some more Hendrix material of questionable value to his fans.
By the way, is Summer of Love supposed to be the name of the CD?