This is an easy one: (compat/sendmail/sendmail.c, around line 375) (wdiff format -- that's wisner diff) if (!binary) { ! for (; optind < argc; ++optind) { + cp = strchr(argv[optind], '\0'); + if (*--cp == ',') + *cp = '\0'; ! (void) fprintf(mfp, "to %s\n", argv[optind]); ! } }