triplets-spin contamination

[milianb]

Dear users,
I am calculating vertical transition energies to the triplet states (rpat option) at the DFT level, and I find that the expectation S^2 value for the lowest triplet states is too high: 2.70, 2.90 (instead of the theoretical value of 2) Has anybody encountered this problem before? Any hint on how to deal with it?
Thank you
Begoña