diff -udrN src.orig/accept.c src/accept.c
--- src.orig/accept.c	Thu Sep  6 15:25:28 2001
+++ src/accept.c	Thu Sep  6 15:28:03 2001
@@ -2140,7 +2140,7 @@
 anything until the terminating dot line is sent. */
 
 if (fflush(data_file) == EOF || ferror(data_file) ||
-    fsync(fileno(data_file)) < 0 || (accept_ferror)(fin))
+    (perform_fsync && fsync(fileno(data_file))) < 0 || (accept_ferror)(fin))
   {
   char *msg_errno = strerror(errno);
   BOOL input_error = (accept_ferror)(fin) != 0;
diff -udrN src.orig/deliver.c src/deliver.c
--- src.orig/deliver.c	Thu Sep  6 15:25:28 2001
+++ src/deliver.c	Thu Sep  6 15:29:22 2001
@@ -578,7 +578,8 @@
   {
   BOOL return_output = FALSE;
   struct stat statbuf;
-  fsync(addr->return_file);
+  if (perform_fsync)
+    fsync(addr->return_file);
 
   /* If there is no output, do nothing. */
 
@@ -1580,7 +1581,7 @@
 
   /* Ensure the journal file is pushed out to disc. */
 
-  if (fsync(journal_fd) < 0)
+  if (perform_fsync && fsync(journal_fd) < 0)
     log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
       strerror(errno));
   }
diff -udrN src.orig/globals.c src/globals.c
--- src.orig/globals.c	Thu Sep  6 15:25:28 2001
+++ src/globals.c	Thu Sep  6 15:24:49 2001
@@ -494,6 +494,7 @@
 BOOL   parse_allow_group      = FALSE;
 BOOL   parse_found_group      = FALSE;
 char  *percent_hack_domains   = NULL;
+BOOL   perform_fsync          = TRUE;
 char  *pid_file_path          = PID_FILE_PATH
 			  "\0<--------------Space to patch pid_file_path->";
 BOOL   preserve_message_logs  = FALSE;
diff -udrN src.orig/globals.h src/globals.h
--- src.orig/globals.h	Thu Sep  6 15:25:28 2001
+++ src/globals.h	Thu Sep  6 15:41:35 2001
@@ -364,6 +364,7 @@
 extern BOOL   parse_allow_group;      /* Allow group syntax */
 extern BOOL   parse_found_group;      /* In the middle of a group */
 extern char  *percent_hack_domains;   /* Local domains for which '% operates */
+extern BOOL   perform_fsync;          /* Use fsync() to flush to disk */
 extern char  *pid_file_path;          /* For writing daemon pids */
 extern BOOL   preserve_message_logs;  /* Save msglog files */
 extern char  *primary_hostname;       /* Primary name of this computer */
diff -udrN src.orig/readconf.c src/readconf.c
--- src.orig/readconf.c	Thu Sep  6 15:25:28 2001
+++ src/readconf.c	Thu Sep  6 15:24:19 2001
@@ -81,6 +81,7 @@
   { "finduser_retries",         opt_int,         &finduser_retries },
   { "forbid_domain_literals",   opt_bool,        &forbid_domain_literals },
   { "freeze_tell_mailmaster",   opt_bool,        &freeze_tell_mailmaster },
+  { "fsync",			opt_bool,        &perform_fsync },
   { "gecos_name",               opt_stringptr,   &gecos_name },
   { "gecos_pattern",            opt_stringptr,   &gecos_pattern },
   { "headers_check_syntax",     opt_bool,        &headers_check_syntax },
diff -udrN src.orig/spool_out.c src/spool_out.c
--- src.orig/spool_out.c	Thu Sep  6 15:25:28 2001
+++ src/spool_out.c	Thu Sep  6 15:29:51 2001
@@ -277,7 +277,7 @@
 just pushes it out of C, and fclose() doesn't guarantee to do the write
 either. That's just the way Unix works... */
 
-if (fsync(fileno(f)) < 0)
+if (perform_fsync && fsync(fileno(f)) < 0)
   return spool_write_error(where, errmsg, "sync", temp_name, f);
 
 /* Get the size of the file, and close it. */
diff -udrN src.orig/transports/appendfile.c src/transports/appendfile.c
--- src.orig/transports/appendfile.c	Thu Sep  6 15:25:28 2001
+++ src/transports/appendfile.c	Thu Sep  6 15:31:40 2001
@@ -2556,7 +2556,7 @@
 /* Force out the remaining data to check for any errors; some OS don't allow
 fsync() to be called for a FIFO. */
 
-if (yield == OK && !isfifo && fsync(fd) < 0) yield = DEFER;
+if (perform_fsync && yield == OK && !isfifo && fsync(fd) < 0) yield = DEFER;
 
 /* Handle error while writing the file. Control should come here directly after
 the error, with the reason in errno. In the case of expansion failure in prefix
diff -udrN src.orig/transports/smtp.c src/transports/smtp.c
--- src.orig/transports/smtp.c	Thu Sep  6 15:25:28 2001
+++ src/transports/smtp.c	Thu Sep  6 15:31:55 2001
@@ -1462,7 +1462,7 @@
 
     /* Ensure the journal file is pushed out to disc. */
 
-    if (fsync(journal_fd) < 0)
+    if (perform_fsync && fsync(journal_fd) < 0)
       log_write(0, LOG_MAIN|LOG_PANIC, "failed to fsync journal: %s",
         strerror(errno));
     }