diff --git a/docs/sources/reference/builder.md b/docs/sources/reference/builder.md
index 46d0e21e88..adf42ae764 100644
--- a/docs/sources/reference/builder.md
+++ b/docs/sources/reference/builder.md
@@ -280,8 +280,14 @@ The cache for `RUN` instructions can be invalidated by `ADD` instructions. See
 
 - [Issue 783](https://github.com/docker/docker/issues/783) is about file
   permissions problems that can occur when using the AUFS file system. You
-  might notice it during an attempt to `rm` a file, for example. The issue
-  describes a workaround.
+  might notice it during an attempt to `rm` a file, for example.
+
+  For systems that have recent aufs version (i.e., `dirperm1` mount option can
+  be set), docker will attempt to fix the issue automatically by mounting
+  the layers with `dirperm1` option. More details on `dirperm1` option can be
+  found at [`aufs` man page](http://aufs.sourceforge.net/aufs3/man.html)
+
+  If your system doesnt have support for `dirperm1`, the issue describes a workaround.
 
 ## CMD