diff -ur mrbayes-3.1.2.orig/bayes.c mrbayes-3.1.2/bayes.c
--- mrbayes-3.1.2.orig/bayes.c	2005-12-24 05:26:28.000000000 +1300
+++ mrbayes-3.1.2/bayes.c	2007-08-17 12:01:08.522168050 +1200
@@ -661,7 +661,7 @@
 	chainParams.printFreq = 100;                     /* frequency to print chain                      */
 	chainParams.swapFreq = 1;                        /* frequency of attempting swap of states        */
 	chainParams.numSwaps = 1;                        /* number of swaps to try each time              */
-	chainParams.mcmcDiagn = YES;                     /* write MCMC diagnostics to file ?              */
+	chainParams.mcmcDiagn = NO;                      /* write MCMC diagnostics to file ?              */
 	chainParams.diagnFreq = 1000;                    /* diagnostics frequency                         */
 	chainParams.minPartFreq = 0.10;                  /* min partition frequency for diagnostics       */
 	chainParams.allChains = NO;                      /* calculate diagnostics for all chains ?        */