diff --git a/lib/html2text.php b/lib/html2text.php
index 9cc213ddd60..e360b2c47d2 100644
--- a/lib/html2text.php
+++ b/lib/html2text.php
@@ -543,9 +543,15 @@ class html2text
      */
     function _convert_pre(&$text)
     {
-        while(preg_match('/<pre[^>]*>(.*)<\/pre>/ismU', $text, $matches)) {
-            $result = preg_replace($this->pre_search, $this->pre_replace, $matches[1]);
-            $text = preg_replace('/<pre[^>]*>.*<\/pre>/ismU', '<div><br>' . $result . '<br></div>', $text, 1);
+         while (preg_match('/<pre[^>]*>(.*)<\/pre>/ismU', $text, $matches)) {
+            // convert the content
+            $this->pre_content = sprintf('<div><br>%s<br></div>',
+                preg_replace($this->pre_search, $this->pre_replace, $matches[1]));
+            // replace the content (use callback because content can contain $0 variable)
+            $text = preg_replace_callback('/<pre[^>]*>.*<\/pre>/ismU',
+                array('html2text', '_preg_pre_callback'), $text, 1);
+            // free memory
+            $this->pre_content = '';
         }
     }
 
@@ -573,6 +579,17 @@ class html2text
         }
     }
 
+    /**
+     *  Callback function for preg_replace_callback use in PRE content handler.
+     *
+     *  @param  array PREG matches
+     *  @return string
+     */
+    private function _preg_pre_callback($matches)
+    {
+        return $this->pre_content;
+    }
+
     /**
      *  Strtoupper multibyte wrapper function
      *
diff --git a/lib/simpletest/testweblib.php b/lib/simpletest/testweblib.php
index cf2c84bc8b5..27359ce88a5 100644
--- a/lib/simpletest/testweblib.php
+++ b/lib/simpletest/testweblib.php
@@ -139,6 +139,27 @@ class web_test extends UnitTestCase {
         $this->assertIdentical('0', html_to_text('0'));
     }
 
+    public function test_html_to_text_pre_parsing_problem() {
+        $strorig = 'Consider the following function:<br /><pre><span style="color: rgb(153, 51, 102);">void FillMeUp(char* in_string) {'.
+                   '<br />  int i = 0;<br />  while (in_string[i] != \'\0\') {<br />    in_string[i] = \'X\';<br />    i++;<br />  }<br />'.
+                   '}</span></pre>What would happen if a non-terminated string were input to this function?<br /><br />';
+
+        $strconv = 'Consider the following function:
+
+void FillMeUp(char* in_string) {
+ int i = 0;
+ while (in_string[i] != \'\0\') {
+ in_string[i] = \'X\';
+ i++;
+ }
+}
+What would happen if a non-terminated string were input to this function?
+
+';
+
+        $this->assertIdentical($strconv, html_to_text($strorig));
+    }
+
     public function test_clean_text() {
         $text = "lala <applet>xx</applet>";
         $this->assertEqual($text, clean_text($text, FORMAT_PLAIN));