Version 2.2-3 of the coxme package has been posted to CRAN. It should propogate to the mirrors over the next 1-2 days. Version 2.2-2 had a serious bug in the lmekin function. If the variance matrix of the random effects was not diagonal the answers were wrong: at one spot an upper triangular matrix U was being used when tr(U) was called for. This affects genetic models in particular. A new test case with known solution has now been added as to the package as well. There was no issue with any of the other functions, e.g., coxme. This pointed out to me by Paola Sebastiani just after 2-2 was posted and just before I left on a trip. I really appreciate the bug report, but the timing was clearly Murphy's law at work. Terry Therneau