diff --git a/plugin/captcha/info.php b/plugin/captcha/info.php
new file mode 100644
index 000000000..ede5d1704
--- /dev/null
+++ b/plugin/captcha/info.php
@@ -0,0 +1,17 @@
+<?php
+include_once("./_common.php");
+
+// prepare an array of wavfiles
+$lc ='/home/tmp/g4s/plugin/captcha/wavs/';
+$wav = $lc.'captcha.wav';
+
+$fields = join('/',array( 'H8ChunkID', 'VChunkSize', 'H8Format',
+                          'H8Subchunk1ID', 'VSubchunk1Size',
+                          'vAudioFormat', 'vNumChannels', 'VSampleRate',
+                          'VByteRate', 'vBlockAlign', 'vBitsPerSample' ));
+
+$fp     = fopen($wav,'rb');
+$header = fread($fp,36);
+$info   = unpack($fields,$header);
+print_r2($info);
+?>
\ No newline at end of file
diff --git a/plugin/captcha/wav.php b/plugin/captcha/wav.php
index c3958ea9b..74f638d5b 100644
--- a/plugin/captcha/wav.php
+++ b/plugin/captcha/wav.php
@@ -42,8 +42,8 @@ function joinwavs($wavs)
                               'H8Subchunk1ID', 'VSubchunk1Size',
                               'vAudioFormat', 'vNumChannels', 'VSampleRate',
                               'VByteRate', 'vBlockAlign', 'vBitsPerSample' ));
-
     $data = '';
+    $info = array();
     foreach($wavs as $wav){
         $fp     = fopen($wav,'rb');
         $header = fread($fp,36);
@@ -65,8 +65,20 @@ function joinwavs($wavs)
         $data .= fread($fp,$size);
     }
 
-    return $header.pack('V',strlen($data)).$data;
+    return ''
+        .pack('a4', 'RIFF')
+        .pack('V', strlen($data) + 36)
+        .pack('a4', 'WAVE')
+        .pack('a4', 'fmt ')
+        .pack('V', $info['Subchunk1Size'])  // 16
+        .pack('v', $info['AudioFormat'])    // 1
+        .pack('v', $info['NumChannels'])    // 1
+        .pack('V', $info['SampleRate'])     // 8000
+        .pack('V', $info['ByteRate'])       // 8000
+        .pack('v', $info['BlockAlign'])     // 1
+        .pack('v', $info['BitsPerSample'])  // 8
+        .pack('a4', 'data')
+        .pack('V', strlen($data))
+        .$data;
 }
-
-exit;
 ?>
diff --git a/plugin/captcha/wavs/captcha.wav b/plugin/captcha/wavs/captcha.wav
new file mode 100644
index 000000000..94dd1f7d6
Binary files /dev/null and b/plugin/captcha/wavs/captcha.wav differ