diff --git a/protocols/rdp/.gitignore b/protocols/rdp/.gitignore
index e37f9166..3f725332 100644
--- a/protocols/rdp/.gitignore
+++ b/protocols/rdp/.gitignore
@@ -21,7 +21,8 @@ Makefile
 Makefile.in
 aclocal.m4
 autom4te.cache/
-m4/
+m4/*
+!README
 config.guess
 config.log
 config.status
diff --git a/protocols/rdp/m4/README b/protocols/rdp/m4/README
new file mode 100644
index 00000000..c9c9cbc4
--- /dev/null
+++ b/protocols/rdp/m4/README
@@ -0,0 +1,12 @@
+This file exists such that the m4/ directory will be created when cloning the
+git repository.
+
+The m4/ directory is not directly used by this project, but libtoolize
+populates this directory with files, recommending that the directory be
+included in the macro search path for aclocal.
+
+Because autoreconf runs aclocal before libtoolize, this directory will not
+exist when autoreconf is run, triggering an error from aclocal.
+
+Creating this directory (and keeping this file in it as a placeholder)
+prevents this error.