diff --git a/wp-admin/install.php b/wp-admin/install.php
index 814803d9ff..dd7380e8f6 100644
--- a/wp-admin/install.php
+++ b/wp-admin/install.php
@@ -138,6 +138,7 @@ flush();
 // Set everything up
 make_db_current_silent();
 populate_options();
+populate_roles();
 
 $wpdb->query("UPDATE $wpdb->options SET option_value = '$weblog_title' WHERE option_name = 'blogname'");
 $wpdb->query("UPDATE $wpdb->options SET option_value = '$admin_email' WHERE option_name = 'admin_email'");
@@ -196,7 +197,6 @@ http://wordpress.org/
 
 @wp_mail($admin_email, __('New WordPress Blog'), $message, $message_headers);
 
-upgrade_all();
 ?>
 
 <p><em><?php _e('Finished!'); ?></em></p>
diff --git a/wp-admin/upgrade-functions.php b/wp-admin/upgrade-functions.php
index 238819317f..3ad6d9bbca 100644
--- a/wp-admin/upgrade-functions.php
+++ b/wp-admin/upgrade-functions.php
@@ -4,13 +4,38 @@ require_once(ABSPATH . '/wp-admin/admin-functions.php');
 require_once(ABSPATH . '/wp-admin/upgrade-schema.php');
 // Functions to be called in install and upgrade scripts
 function upgrade_all() {
+	global $wp_current_db_version, $wp_db_version;
+	$wp_current_db_version = __get_option('db_version');
+
+	// We are up-to-date.  Nothing to do.
+	if ( $wp_db_version == $wp_current_db_version )
+		return;
+
+	// If the version is not set in the DB, try to guess the version.
+	if ( empty($wp_current_db_version) ) {
+		$wp_current_db_version = 0;
+
+		// If the template option exists, we have 1.5.
+		$template = __get_option('template');
+		if ( !empty($template) )
+			$wp_current_db_version = 2541;
+	}
+	
 	populate_options();
-	upgrade_100();
-	upgrade_101();
-	upgrade_110();
-	upgrade_130();
-	upgrade_160();
+
+	if ( $wp_current_db_version < 2541 ) {
+		upgrade_100();
+		upgrade_101();
+		upgrade_110();
+		upgrade_130();
+	}
+	
+	if ( $wp_current_db_version < 2966 )
+		upgrade_160();
+
 	save_mod_rewrite_rules();
+	
+	update_option('db_version', $wp_db_version);
 }
 
 function upgrade_100() {
@@ -82,18 +107,16 @@ function upgrade_101() {
 
 
 function upgrade_110() {
-  global $wpdb;
+	global $wpdb;
 	
     // Set user_nicename.
-	// FIXME: user_nickname is no longer in the user table.  Need to update and
-	// move this code to where the new usermeta table is setup.
-//  $users = $wpdb->get_results("SELECT ID, user_nickname, user_nicename FROM $wpdb->users");
-// 	foreach ($users as $user) {
-// 		if ('' == $user->user_nicename) { 
-// 			$newname = sanitize_title($user->user_nickname);
-// 			$wpdb->query("UPDATE $wpdb->users SET user_nicename = '$newname' WHERE ID = '$user->ID'");
-// 		}
-// 	}
+	$users = $wpdb->get_results("SELECT ID, user_nickname, user_nicename FROM $wpdb->users");
+ 	foreach ($users as $user) {
+ 		if ('' == $user->user_nicename) { 
+ 			$newname = sanitize_title($user->user_nickname);
+ 			$wpdb->query("UPDATE $wpdb->users SET user_nicename = '$newname' WHERE ID = '$user->ID'");
+ 		}
+ 	}
 
 	$users = $wpdb->get_results("SELECT ID, user_pass from $wpdb->users");
 	foreach ($users as $row) {
@@ -218,6 +241,9 @@ function upgrade_130() {
 
 function upgrade_160() {
 	global $wpdb, $table_prefix;
+	
+	populate_roles_160();
+
 	$users = $wpdb->get_results("SELECT * FROM $wpdb->users");
 	foreach ( $users as $user ) :
 		if ( !empty( $user->user_firstname ) )
diff --git a/wp-admin/upgrade-schema.php b/wp-admin/upgrade-schema.php
index a6df3d5b82..630100b9a7 100644
--- a/wp-admin/upgrade-schema.php
+++ b/wp-admin/upgrade-schema.php
@@ -222,8 +222,6 @@ function populate_options() {
 	add_option('default_role', 'inactive');
 	add_option('rich_editing', 'true');
 
-	populate_roles();
-
 	// Delete unused options
 	$unusedoptions = array ('blodotgsping_url', 'bodyterminator', 'emailtestonly', 'phoneemail_separator', 'smilies_directory', 'subjectprefix', 'use_bbcode', 'use_blodotgsping', 'use_phoneemail', 'use_quicktags', 'use_weblogsping', 'weblogs_cache_file', 'use_preview', 'use_htmltrans', 'smilies_directory', 'fileupload_allowedusers', 'use_phoneemail', 'default_post_status', 'default_post_category', 'archive_mode', 'time_difference', 'links_minadminlevel', 'links_use_adminlevels', 'links_rating_type', 'links_rating_char', 'links_rating_ignore_zero', 'links_rating_single_image', 'links_rating_image0', 'links_rating_image1', 'links_rating_image2', 'links_rating_image3', 'links_rating_image4', 'links_rating_image5', 'links_rating_image6', 'links_rating_image7', 'links_rating_image8', 'links_rating_image9', 'weblogs_cacheminutes', 'comment_allowed_tags', 'search_engine_friendly_urls', 'default_geourl_lat', 'default_geourl_lon', 'use_default_geourl', 'weblogs_xml_url', 'new_users_can_blog');
 	foreach ($unusedoptions as $option) :
@@ -238,6 +236,10 @@ function populate_options() {
 }
 
 function populate_roles() {
+	populate_roles_160();	
+}
+
+function populate_roles_160() {
 	global $wp_roles;
 
 	// Add roles
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 1c31ee7d37..01ac776764 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -3,5 +3,6 @@
 // This just holds the version number, in a separate file so we can bump it without cluttering the SVN
 
 $wp_version = '1.6-ALPHA-2-still-dont-use';
+$wp_db_version = 2966;
 
 ?>
\ No newline at end of file