Unfortunately you will have to have 9 pairs of players who play together twice. This posting explains why.
Here is a schedule that you could use. No player plays in the same position within a foursome more than once.
(4 2 3 1) (10 8 6 5) (7 12 9 11)
(5 10 12 4) (11 9 8 2) (3 6 1 7)
(2 7 5 6) ( 1 11 10 12) (8 3 4 9)
Hope that helps,
Ian.