diff --git a/framework/Smtp/lib/Horde/Smtp/Filter/Data.php b/framework/Smtp/lib/Horde/Smtp/Filter/Data.php
index 2ea78c12460..b65ab68085c 100644
--- a/framework/Smtp/lib/Horde/Smtp/Filter/Data.php
+++ b/framework/Smtp/lib/Horde/Smtp/Filter/Data.php
@@ -48,7 +48,7 @@ public function filter($in, $out, &$consumed, $closing)
             // EOLs need to be CRLF; double leading periods.
             $bucket->data = preg_replace(
                 array("/(?:\r\n|\n|\r(?!\n))/", "/\n\./"),
-                array("\r\n", '..'),
+                array("\r\n", "\n.."),
                 $bucket->data
             );
 
diff --git a/framework/Smtp/package.xml b/framework/Smtp/package.xml
index 3243b389ce9..c727c5d5f9f 100644
--- a/framework/Smtp/package.xml
+++ b/framework/Smtp/package.xml
@@ -10,7 +10,7 @@
   <email>slusarz@horde.org</email>
   <active>yes</active>
  </lead>
- <date>2013-10-15</date>
+ <date>2013-10-19</date>
  <version>
   <release>1.2.5</release>
   <api>1.2.0</api>
@@ -21,7 +21,7 @@
  </stability>
  <license uri="http://www.horde.org/licenses/lgpl21">LGPL-2.1</license>
  <notes>
-* 
+* [mms] Fix escaping periods that begin a line of DATA input.
  </notes>
  <contents>
   <dir baseinstalldir="/" name="/">
@@ -59,6 +59,7 @@
       <file name="AllTests.php" role="test" />
       <file name="bootstrap.php" role="test" />
       <file name="conf.php.dist" role="test" />
+      <file name="FilterDataTest.php" role="test" />
       <file name="phpunit.xml" role="test" />
       <file name="RemoteServerTest.php" role="test" />
      </dir> <!-- /test/Horde/Smtp -->
@@ -142,6 +143,7 @@
    <install as="Horde/Smtp/AllTests.php" name="test/Horde/Smtp/AllTests.php" />
    <install as="Horde/Smtp/bootstrap.php" name="test/Horde/Smtp/bootstrap.php" />
    <install as="Horde/Smtp/conf.php.dist" name="test/Horde/Smtp/conf.php.dist" />
+   <install as="Horde/Smtp/FilterDataTest.php" name="test/Horde/Smtp/FilterDataTest.php" />
    <install as="Horde/Smtp/phpunit.xml" name="test/Horde/Smtp/phpunit.xml" />
    <install as="Horde/Smtp/RemoteServerTest.php" name="test/Horde/Smtp/RemoteServerTest.php" />
   </filelist>
@@ -253,10 +255,10 @@
    <stability>
     <release>stable</release>
     <api>stable</api></stability>
-   <date>2013-10-15</date>
+   <date>2013-10-19</date>
    <license uri="http://www.horde.org/licenses/lgpl21">LGPL-2.1</license>
    <notes>
-* 
+* [mms] Fix escaping periods that begin a line of DATA input.
    </notes>
   </release>
  </changelog>
diff --git a/framework/Smtp/test/Horde/Smtp/FilterDataTest.php b/framework/Smtp/test/Horde/Smtp/FilterDataTest.php
new file mode 100644
index 00000000000..e74cb63ca12
--- /dev/null
+++ b/framework/Smtp/test/Horde/Smtp/FilterDataTest.php
@@ -0,0 +1,53 @@
+<?php
+/**
+ * Copyright 2013 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file COPYING for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @category   Horde
+ * @copyright  2013 Horde LLC
+ * @license    http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @package    Smtp
+ * @subpackage UnitTests
+ */
+
+/**
+ * Test for the SMTP DATA filter.
+ *
+ * @author     Michael Slusarz <slusarz@horde.org>
+ * @category   Horde
+ * @copyright  2013 Horde LLC
+ * @ignore
+ * @license    http://www.horde.org/licenses/lgpl21 LGPL 2.1
+ * @package    Smtp
+ * @subpackage UnitTests
+ */
+class Horde_Smtp_FilterDataTest extends Horde_Test_Case
+{
+    private $stream;
+
+    public function setUp()
+    {
+        $this->stream = fopen('php://temp', 'r+');
+        stream_filter_register('horde_smtp_data', 'Horde_Smtp_Filter_Data');
+        stream_filter_append($this->stream, 'horde_smtp_data', STREAM_FILTER_READ);
+    }
+
+    public function tearDown()
+    {
+        fclose($this->stream);
+    }
+
+    public function testLeadingPeriodsEscape()
+    {
+        fwrite($this->stream, "Foo\r\n.\r\nFoo\r\n");
+        rewind($this->stream);
+
+        $this->assertEquals(
+            "Foo\r\n..\r\nFoo\r\n",
+            stream_get_contents($this->stream)
+        );
+    }
+
+}