This patch from Antti Tapaninen added the --omit-dir-changes option, which
tells rsync to not affect any attributes on the directories in the transfer.

To use this patch, run these commands for a successful build:

    patch -p1 <patches/omit-dir-changes.diff
    ./configure                              (optional if already run)
    make

based-on: 0ac7ebceef70417355f25daf9e2fd94e84c49749
diff --git a/generator.c b/generator.c
--- a/generator.c
+++ b/generator.c
@@ -47,6 +47,7 @@ extern int preserve_perms;
 extern int preserve_mtimes;
 extern int omit_dir_times;
 extern int omit_link_times;
+extern int omit_dir_changes;
 extern int delete_mode;
 extern int delete_before;
 extern int delete_during;
@@ -506,6 +507,7 @@ void itemize(const char *fnamecmp, struct file_struct *file, int ndx, int statre
 	     const char *xname)
 {
 	if (statret >= 0) { /* A from-dest-dir statret can == 1! */
+		int omit_changes = omit_dir_changes && S_ISDIR(sxp->st.st_mode);
 		int keep_time = !preserve_mtimes ? 0
 		    : S_ISDIR(file->mode) ? !omit_dir_times
 		    : S_ISLNK(file->mode) ? !omit_link_times
@@ -543,9 +545,9 @@ void itemize(const char *fnamecmp, struct file_struct *file, int ndx, int statre
 		} else if (preserve_executability
 		 && ((sxp->st.st_mode & 0111 ? 1 : 0) ^ (file->mode & 0111 ? 1 : 0)))
 			iflags |= ITEM_REPORT_PERMS;
-		if (uid_ndx && am_root && (uid_t)F_OWNER(file) != sxp->st.st_uid)
+		if (uid_ndx && am_root && !omit_changes && (uid_t)F_OWNER(file) != sxp->st.st_uid)
 			iflags |= ITEM_REPORT_OWNER;
-		if (gid_ndx && !(file->flags & FLAG_SKIP_GROUP) && sxp->st.st_gid != (gid_t)F_GROUP(file))
+		if (gid_ndx && !omit_changes && !(file->flags & FLAG_SKIP_GROUP) && sxp->st.st_gid != (gid_t)F_GROUP(file))
 			iflags |= ITEM_REPORT_GROUP;
 #ifdef SUPPORT_ACLS
 		if (preserve_acls && !S_ISLNK(file->mode)) {
@@ -1448,7 +1450,7 @@ static void recv_generator(char *fname, struct file_struct *file, int ndx,
 		real_ret = statret;
 		if (file->flags & FLAG_DIR_CREATED)
 			statret = -1;
-		if (!preserve_perms) { /* See comment in non-dir code below. */
+		if (!preserve_perms || omit_dir_changes) { /* See comment in non-dir code below. */
 			file->mode = dest_mode(file->mode, sx.st.st_mode, dflt_perms, statret == 0);
 		}
 		if (statret != 0 && basis_dir[0] != NULL) {
diff --git a/options.c b/options.c
--- a/options.c
+++ b/options.c
@@ -77,6 +77,7 @@ int delete_before = 0;
 int delete_after = 0;
 int delete_excluded = 0;
 int remove_source_files = 0;
+int omit_dir_changes = 0;
 int one_file_system = 0;
 int protocol_version = PROTOCOL_VERSION;
 int sparse_files = 0;
@@ -643,6 +644,7 @@ static struct poptOption long_options[] = {
   {"omit-link-times", 'J', POPT_ARG_VAL,    &omit_link_times, 1, 0, 0 },
   {"no-omit-link-times",0, POPT_ARG_VAL,    &omit_link_times, 0, 0, 0 },
   {"no-J",             0,  POPT_ARG_VAL,    &omit_link_times, 0, 0, 0 },
+  {"omit-dir-changes", 0,  POPT_ARG_NONE,   &omit_dir_changes, 0, 0, 0 },
   {"modify-window",   '@', POPT_ARG_INT,    &modify_window, OPT_MODIFY_WINDOW, 0, 0 },
   {"super",            0,  POPT_ARG_VAL,    &am_root, 2, 0, 0 },
   {"no-super",         0,  POPT_ARG_VAL,    &am_root, 0, 0, 0 },
@@ -2296,6 +2298,9 @@ int parse_arguments(int *argc_p, const char ***argv_p)
 		parse_filter_str(&filter_list, backup_dir_buf, rule_template(0), 0);
 	}
 
+	if (omit_dir_changes)
+		omit_dir_times = 1;
+
 	if (make_backups && !backup_dir)
 		omit_dir_times = -1; /* Implied, so avoid -O to sender. */
 
@@ -2792,6 +2797,8 @@ void server_options(char **args, int *argc_p)
 			args[ac++] = "--size-only";
 		if (do_stats)
 			args[ac++] = "--stats";
+		if (omit_dir_changes)
+			args[ac++] = "--omit-dir-changes";
 	} else {
 		if (skip_compress)
 			args[ac++] = safe_arg("--skip-compress", skip_compress);
diff --git a/rsync.1.md b/rsync.1.md
--- a/rsync.1.md
+++ b/rsync.1.md
@@ -383,6 +383,7 @@ has its own detailed description later in this manpage.
 --crtimes, -N            preserve create times (newness)
 --omit-dir-times, -O     omit directories from --times
 --omit-link-times, -J    omit symlinks from --times
+--omit-dir-changes       omit directories from any attribute changes
 --super                  receiver attempts super-user activities
 --fake-super             store/recover privileged attrs using xattrs
 --sparse, -S             turn sequences of nulls into sparse blocks
@@ -1549,6 +1550,11 @@ your home directory (remove the '=' for that).
     This tells rsync to omit symlinks when it is preserving modification,
     access, and create times.
 
+0.  `--omit-dir-changes`
+
+    This tells rsync to omit directories when applying any preserved attributes
+    (owner, group, times, permissions) to already existing directories.
+
 0.  `--super`
 
     This tells the receiving side to attempt super-user activities even if the
diff --git a/rsync.c b/rsync.c
--- a/rsync.c
+++ b/rsync.c
@@ -35,6 +35,7 @@ extern int preserve_executability;
 extern int preserve_mtimes;
 extern int omit_dir_times;
 extern int omit_link_times;
+extern int omit_dir_changes;
 extern int am_root;
 extern int am_server;
 extern int am_daemon;
@@ -520,9 +521,11 @@ int set_file_attrs(const char *fname, struct file_struct *file, stat_x *sxp,
 		get_acl(fname, sxp);
 #endif
 
-	change_uid = am_root && uid_ndx && sxp->st.st_uid != (uid_t)F_OWNER(file);
+	change_uid = am_root && uid_ndx && sxp->st.st_uid != (uid_t)F_OWNER(file)
+		  && !(omit_dir_changes && S_ISDIR(sxp->st.st_mode));
 	change_gid = gid_ndx && !(file->flags & FLAG_SKIP_GROUP)
-		  && sxp->st.st_gid != (gid_t)F_GROUP(file);
+		  && sxp->st.st_gid != (gid_t)F_GROUP(file)
+		  && !(omit_dir_changes && S_ISDIR(sxp->st.st_mode));
 #ifndef CAN_CHOWN_SYMLINK
 	if (S_ISLNK(sxp->st.st_mode)) {
 		;
diff -Nurp a/rsync.1 b/rsync.1
--- a/rsync.1
+++ b/rsync.1
@@ -460,6 +460,7 @@ has its own detailed description later i
 --crtimes, -N            preserve create times (newness)
 --omit-dir-times, -O     omit directories from --times
 --omit-link-times, -J    omit symlinks from --times
+--omit-dir-changes       omit directories from any attribute changes
 --super                  receiver attempts super-user activities
 --fake-super             store/recover privileged attrs using xattrs
 --sparse, -S             turn sequences of nulls into sparse blocks
@@ -1623,6 +1624,9 @@ sub-directories when incremental recursi
 .IP "\fB\-\-omit-link-times\fP, \fB\-J\fP"
 This tells rsync to omit symlinks when it is preserving modification,
 access, and create times.
+.IP "\fB\-\-omit-dir-changes\fP"
+This tells rsync to omit directories when applying any preserved attributes
+(owner, group, times, permissions) to already existing directories.
 .IP "\fB\-\-super\fP"
 This tells the receiving side to attempt super-user activities even if the
 receiving rsync wasn't run by the super-user.  These activities include:
diff -Nurp a/rsync.1.html b/rsync.1.html
--- a/rsync.1.html
+++ b/rsync.1.html
@@ -378,6 +378,7 @@ has its own detailed description later i
 --crtimes, -N            preserve create times (newness)
 --omit-dir-times, -O     omit directories from --times
 --omit-link-times, -J    omit symlinks from --times
+--omit-dir-changes       omit directories from any attribute changes
 --super                  receiver attempts super-user activities
 --fake-super             store/recover privileged attrs using xattrs
 --sparse, -S             turn sequences of nulls into sparse blocks
@@ -1480,6 +1481,11 @@ sub-directories when incremental recursi
 access, and create times.</p>
 </dd>
 
+<dt id="opt--omit-dir-changes"><code>--omit-dir-changes</code><a href="#opt--omit-dir-changes" class="tgt"></a></dt><dd>
+<p>This tells rsync to omit directories when applying any preserved attributes
+(owner, group, times, permissions) to already existing directories.</p>
+</dd>
+
 <dt id="opt--super"><code>--super</code><a href="#opt--super" class="tgt"></a></dt><dd>
 <p>This tells the receiving side to attempt super-user activities even if the
 receiving rsync wasn't run by the super-user.  These activities include:
