diff --git a/common.php b/common.php
index 9d22a24..422b6d9 100644
--- a/common.php
+++ b/common.php
@@ -13,9 +13,9 @@ function debug($msg, $exit = false) {
 	global $trace;
 	if ($trace) {
 		if (is_array($msg)) {
-			print_r($msg);
+			//print_r($msg);
 		} else {
-			echo 'debug> ' . $msg;
+			echo '<p>Debug> ' . $msg;
 		}
 		echo "\n";
 	}
@@ -42,7 +42,7 @@ function getUTCTimeStamp() {
 
 // Sign a http query string in the array of key-value pairs
 // return b64 encoded hmac hash
-function sign($a, $apiKey) {
+function sign($a, $apiKey, $debug=false) {
 	ksort($a);
 	$qs = '';
 	$n = count($a);
@@ -56,15 +56,18 @@ function sign($a, $apiKey) {
 	
 	// Generate the signature
 	//debug('API key: '.$apiKey); // API key of the client
-	debug('Signing: '.$qs);
+	debug('SIGN: '.$qs);
 	
 	// the TRUE at the end states we want the raw value, not hexadecimal form
 	$hmac = hash_hmac('sha1', utf8_encode($qs), $apiKey, true);
 	$hmac = base64_encode($hmac);
-	
+	if ($debug) {
+		debug('h='.$hmac);
+		debug('<a href=verify_debug.php?'.$qs.'&h='.urlencode($hmac).'>Submit the request >> </a>');
+	}
 	return $hmac;
 		
-} // SignWithTime
+} // sign an array of query string
 
 function outputToFile($outFname, $content, $mode, $append = false) {
 	$out = fopen($outFname, ($append ? "a" : "w"));
diff --git a/sign_demo.php b/sign_demo.php
new file mode 100644
index 0000000..9797a88
--- /dev/null
+++ b/sign_demo.php
@@ -0,0 +1,37 @@
+<h3>Generate a signature</h3>
+
+<?php require_once '../yubiphpbase/appinclude.php';
+      require_once '../yubiphpbase/yubi_lib.php';
+      require_once 'common.php';
+
+$trace = true;
+
+$act = getHttpVal('act', '');
+
+if ($act == '') {
+	echo '<form action=sign_demo.php method=post>'.
+		'<input name=act value=sign type=hidden>'.
+		'api key: (use your api key issued to you by Yubico in b64 format): ' .
+		'<input name=apikey size=45 maxlength=100 value="kNapft02c1a81N4MEMDcC/mgcGc="><p>'.
+		'id (your client id): <input name=id size=5 maxlength=10><p>'.	
+		'otp: <input name=otp size=45 maxlength=100><p>'.
+		'<input type=submit value=Sign>'.
+		'</form>';
+	exit;
+}
+
+$id = getHttpVal('id', '');
+$otp = getHttpVal('otp', '');
+$t = getHttpVal('t', '');
+$apiKey = base64_decode(getHttpVal('apikey', ''));
+
+$a['id']=$id;
+$a['otp']=$otp;
+
+if ($t != '') {
+  $a['t']=$t;
+}
+
+$hmac = sign($a, $apiKey, true);
+
+?>
diff --git a/verifyOTP.php b/verifyOTP.php
index df7c577..1957509 100644
--- a/verifyOTP.php
+++ b/verifyOTP.php
@@ -24,7 +24,6 @@ if ($otp == '') {
 //
 $devId = substr($otp, 0, 12);
 $ad = getAuthData($devId);
-debug('Auth Data from DB:');
 
 if ($ad == null) {
 	debug('Invalid Yubikey '.$devId);