diff --git a/Doxyfile b/Doxyfile
index 417ed045..da12f467 100644
--- a/Doxyfile
+++ b/Doxyfile
@@ -31,7 +31,7 @@ PROJECT_NAME           = HTMLPurifier
 # This could be handy for archiving the generated documentation or 
 # if some version control system is used.
 
-PROJECT_NUMBER         = 3.1.0
+PROJECT_NUMBER         = 3.1.0-dev
 
 # The OUTPUT_DIRECTORY tag is used to specify the (relative or absolute) 
 # base path where the generated documentation will be put. 
diff --git a/NEWS b/NEWS
index 7007d737..6d0d2539 100644
--- a/NEWS
+++ b/NEWS
@@ -9,7 +9,7 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
     . Internal change
 ==========================
 
-3.1.0, released 2008-04-24
+3.1.0, unknown release date
 # Unnecessary references to objects (vestiges of PHP4) removed from method
   signatures.  The following methods do not need references when assigning from
   them and will result in E_STRICT errors if you try:
diff --git a/VERSION b/VERSION
index a0cd9f0c..fee2d3e4 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.1.0
\ No newline at end of file
+3.1.0-dev
\ No newline at end of file
diff --git a/configdoc/usage.xml b/configdoc/usage.xml
index 9b04d927..c2eb4413 100644
--- a/configdoc/usage.xml
+++ b/configdoc/usage.xml
@@ -2,7 +2,7 @@
 <usage>
  <directive id="Core.CollectErrors">
   <file name="HTMLPurifier.php">
-   <line>129</line>
+   <line>132</line>
   </file>
   <file name="HTMLPurifier/Lexer.php">
    <line>85</line>
diff --git a/library/HTMLPurifier.includes.php b/library/HTMLPurifier.includes.php
index 0e630b56..e7ba0cc1 100644
--- a/library/HTMLPurifier.includes.php
+++ b/library/HTMLPurifier.includes.php
@@ -7,7 +7,7 @@
  * primary concern and you are using an opcode cache. PLEASE DO NOT EDIT THIS
  * FILE, changes will be overwritten the next time the script is run.
  * 
- * @version 3.1.0
+ * @version 3.1.0-dev
  * 
  * @warning
  *      You must *not* include any other HTML Purifier files before this file,
diff --git a/library/HTMLPurifier.php b/library/HTMLPurifier.php
index 6f65b305..135b9a0d 100644
--- a/library/HTMLPurifier.php
+++ b/library/HTMLPurifier.php
@@ -19,7 +19,7 @@
  */
 
 /*
-    HTML Purifier 3.1.0 - Standards Compliant HTML Filtering
+    HTML Purifier 3.1.0-dev - Standards Compliant HTML Filtering
     Copyright (C) 2006-2008 Edward Z. Yang
 
     This library is free software; you can redistribute it and/or
@@ -55,7 +55,10 @@ class HTMLPurifier
 {
     
     /** Version of HTML Purifier */
-    public $version = '3.1.0';
+    public $version = '3.1.0-dev';
+    
+    /** Constant with version of HTML Purifier */
+    const version = '3.1.0-dev';
     
     /** Global configuration object */
     public $config;
diff --git a/library/HTMLPurifier/Config.php b/library/HTMLPurifier/Config.php
index 3533e573..bb854849 100644
--- a/library/HTMLPurifier/Config.php
+++ b/library/HTMLPurifier/Config.php
@@ -20,7 +20,7 @@ class HTMLPurifier_Config
     /**
      * HTML Purifier's version
      */
-    public $version = '3.1.0';
+    public $version = '3.1.0-dev';
     
     /**
      * Bool indicator whether or not to automatically finalize 
diff --git a/release1-update.php b/release1-update.php
index c611b324..8f02c16b 100644
--- a/release1-update.php
+++ b/release1-update.php
@@ -24,21 +24,23 @@ $version = trim($argv[1]);
 file_put_contents('VERSION', $version);
 
 // ...in NEWS
-$date = date('Y-m-d');
-$news_c = str_replace(
-    $l = "$version, unknown release date",
-    "$version, released $date",
-    file_get_contents('NEWS'),
-    $c
-);
-if (!$c) {
-    echo 'Could not update NEWS, missing ' . $l . PHP_EOL;
-    exit;
-} elseif ($c > 1) {
-    echo 'More than one release declaration in NEWS replaced' . PHP_EOL;
-    exit;
+if ($is_dev = (strpos($version, 'dev') === false)) {
+  $date = date('Y-m-d');
+  $news_c = str_replace(
+      $l = "$version, unknown release date",
+      "$version, released $date",
+      file_get_contents('NEWS'),
+      $c
+  );
+  if (!$c) {
+      echo 'Could not update NEWS, missing ' . $l . PHP_EOL;
+      exit;
+  } elseif ($c > 1) {
+      echo 'More than one release declaration in NEWS replaced' . PHP_EOL;
+      exit;
+  }
+  file_put_contents('NEWS', $news_c);
 }
-file_put_contents('NEWS', $news_c);
 
 // ...in Doxyfile
 $doxyfile_c = preg_replace(
@@ -72,7 +74,17 @@ $htmlpurifier_c = preg_replace(
     1, $c
 );
 if (!$c) {
-    echo 'Could not update HTMLPurifier.php, missing var $version.' . PHP_EOL;
+    echo 'Could not update HTMLPurifier.php, missing public $version.' . PHP_EOL;
+    exit;
+}
+$htmlpurifier_c = preg_replace(
+    '/const version = \'.+?\';/',
+    "const version = '$version';",
+    $htmlpurifier_c,
+    1, $c
+);
+if (!$c) {
+    echo 'Could not update HTMLPurifier.php, missing const $version.' . PHP_EOL;
     exit;
 }
 file_put_contents('library/HTMLPurifier.php', $htmlpurifier_c);
@@ -85,12 +97,12 @@ $config_c = preg_replace(
     1, $c
 );
 if (!$c) {
-    echo 'Could not update Config.php, missing var $version.' . PHP_EOL;
+    echo 'Could not update Config.php, missing public $version.' . PHP_EOL;
     exit;
 }
 file_put_contents('library/HTMLPurifier/Config.php', $config_c);
 
 passthru('php maintenance/flush.php');
 
-echo "Review changes, write something in WHATSNEW, and then SVN commit with log 'Release $version.'" . PHP_EOL;
-
+if ($is_dev) echo "Review changes, write something in WHATSNEW, and then SVN commit with log 'Release $version.'" . PHP_EOL;
+else echo "Numbers updated to dev, no other modifications necessary!";