Index: wp-includes/version.php
===================================================================
--- wp-includes/version.php     (revision 18656)
+++ wp-includes/version.php     (working copy)
@@ -40,3 +40,13 @@
  * @global string $required_mysql_version
  */
 $required_mysql_version = '5.0';
+
+/**
+ * Generates the string for SVN version, if appropriate
+ *
+ * @global string $wp_svn_version
+ */
+if ( $svn = File( '.svn/entries' ) )
+       $wp_svn_version = ' SVN Revision: ' . $svn[3];
+else
+       $wp_svn_version = '';
Index: wp-admin/includes/update.php
===================================================================
--- wp-admin/includes/update.php        (revision 18656)
+++ wp-admin/includes/update.php        (working copy)
@@ -86,7 +86,7 @@
                return false;

        if ( !current_user_can('update_core') )
-               return sprintf( __( 'Version %s' ), $GLOBALS['wp_version'] );
+               return sprintf( __( 'Version %1$s%2$s' ), $GLOBALS['wp_version'], $GLOBALS['wp_svn_version'] );

        $cur = get_preferred_from_update_core();
        if ( ! isset( $cur->current ) )
@@ -100,7 +100,7 @@

        switch ( $cur->response ) {
        case 'development' :
-               return sprintf( __( 'You are using a development version (%1$s). Cool! Please <a href="%2$s">stay updated</a>.' ), $GLOBALS['wp_version'], network_admin_url( 'update-core.php' ) );
+               return sprintf( __( 'You are using a development version (%1$s%2$s). Cool! Please <a href="%3$s">stay updated</a>.' ), $GLOBALS['wp_version'], $GLOBALS['wp_svn_version'], network_admin_url( 'update-core.php' ) );
        break;

        case 'upgrade' :
@@ -109,7 +109,7 @@

        case 'latest' :
        default :
-               return sprintf( __( 'Version %s' ), $GLOBALS['wp_version'] );
+               return sprintf( __( 'Version %1$s%2$s' ), $GLOBALS['wp_version'], $GLOBALS['wp_svn_version'] );
        break;
        }
 }
@@ -145,7 +145,7 @@

        $cur = get_preferred_from_update_core();

-       $msg = sprintf( __('You are using <span class="b">WordPress %s</span>.'), $GLOBALS['wp_version'] );
+       $msg = sprintf( __('You are using <span class="b">WordPress %1$s%2$s</span>.'), $GLOBALS['wp_version'], $GLOBALS['wp_svn_version'] );

        if ( isset( $cur->response ) && $cur->response == 'upgrade' && current_user_can('update_core') ) {
                $msg .= " <a href='" . network_admin_url( 'update-core.php' ) . "' class='button'>" . sprintf( __('Update to %s'), $cur->current ? $cur->current : __( 'Latest' ) ) . '</a>';