NEON optimization of speex

Hi,

We(Linaro) are evaluating to optimize speex using ARM NEON as an open source NEON optimized version is not available. Please let us know if someone is already working on it or if some version exists in the open source community which we might have missed. Secondly,I want to know if bit exactness is mandatory for the NEON optimized version with the C only version? and if a lsb mismatch once in a while is acceptable?