diff --git a/Makefile b/Makefile
index 38dc8d2..e280a81 100644
--- a/Makefile
+++ b/Makefile
@@ -22,7 +22,7 @@ distclean: clean
 	echo -e '<?php\nheader("Location: ./../index.php");\n?>' > ca/index.php
 
 	echo '<?php' > config.php
-	echo 'define(PHPKI_VERSION, "$(VERSION)");' >> config.php
+	echo 'define("PHPKI_VERSION", "$(VERSION)");' >> config.php
 	echo '?>' >> config.php
 
 	rm -f index.php setup.php
diff --git a/config.php b/config.php
index 188ac19..e89a276 100644
--- a/config.php
+++ b/config.php
@@ -1,3 +1,3 @@
 <?php
-define(PHPKI_VERSION, "0.83");
+define("PHPKI_VERSION", "0.83");
 ?>
diff --git a/include/common.php b/include/common.php
index d7a9692..90f078c 100644
--- a/include/common.php
+++ b/include/common.php
@@ -2,7 +2,7 @@
 
 umask(0007);
 
-if ($_SERVER['PHP_AUTH_USER'])
+if (isset($_SERVER['PHP_AUTH_USER']))
 	$PHPki_user = md5($_SERVER['PHP_AUTH_USER']);
 else
 	$PHPki_user = md5('default');
diff --git a/include/my_functions.php b/include/my_functions.php
index 138bc03..ee3f998 100644
--- a/include/my_functions.php
+++ b/include/my_functions.php
@@ -64,8 +64,8 @@ function upload($source, $destination, $content_type="application/octet-stream")
 function gpvar($v) {
 	global $_GET, $_POST;
     $x = "";
-	if ($_GET[$v])  $x = $_GET[$v];
-	if ($_POST[$v]) $x = $_POST[$v];
+	if (isset($_GET[$v]))  $x = $_GET[$v];
+	if (isset($_POST[$v])) $x = $_POST[$v];
 	if (get_magic_quotes_gpc()) $x = stripslashes($x);
 	return $x;
 }
diff --git a/setup.php-presetup b/setup.php-presetup
index b98b8b1..dfa845f 100644
--- a/setup.php-presetup
+++ b/setup.php-presetup
@@ -109,7 +109,7 @@ case 'validate':
 	if ( $passwd and $passwd != $passwdv )
 		$er .= 'Password and password verification do not match.<br>';
 
-        if ( $email && ! is_email($contact) )
+        if ( $contact && ! is_email($contact) )
                 $er .= 'E-mail address ('. htvar($contact) . ') may be invalid.<br>';
 
 	if (strpos($store_dir,$_SERVER['DOCUMENT_ROOT']) === 0)
@@ -739,7 +739,7 @@ E-mail: <a href=mailto:someone@somewhere.com>someone@somewhere.com</a>&nbsp;&nbs
 	<td>
 	<strong>Password</strong> <font color=red>*</font><br>
 	This password will be used to protect your root certificate private
-	key.  <strong><font color=red>Do not lose or forget this password.</font></strong>
+	key.<br/>Can't contain single quote ! <strong><font color=red>Do not lose or forget this password.</font></strong>
 	</td>
 	<td><input type=password name=passwd value="<?=htvar($passwd)?>" size=30>&nbsp;&nbsp; Again <input type=password name=passwdv value="<?=htvar($passwdv)?>" size=30></td>
 	</tr>