A new version of the ULFM specification accounting for remarks and discussions going on at the MPI Forum Meeting in Chicago in December 2013 has been posted under the ULFM Specification item.
This new update adds a new error code to separate process failure errors from non-impacted requests when they remain pending (MPI_ERR_PROC_FAILED_PENDING), and adds new examples.
Head to ULFM Specification for more info.