Index: wp-includes/link-template.php
===================================================================
--- wp-includes/link-template.php	(revision 15448)
+++ wp-includes/link-template.php	(working copy)
@@ -1480,7 +1480,7 @@
  * @param int $max_page Optional. Max pages.
  * @return string|null
  */
-function get_next_posts_link( $label = 'Next Page »', $max_page = 0 ) {
+function get_next_posts_link( $label = 'Next Page »', $max_page = 0, $class='' ) {
 	global $paged, $wp_query;
 
 	if ( !$max_page )
@@ -1492,7 +1492,10 @@
 	$nextpage = intval($paged) + 1;
 
 	if ( !is_single() && ( empty($paged) || $nextpage <= $max_page) ) {
-		$attr = apply_filters( 'next_posts_link_attributes', '' );
+		$attr = '';
+		if ( !empty($class) )
+			$attr = 'class="'. $class . '"';
+		$attr = apply_filters( 'next_posts_link_attributes', $attr );
 		return '<a href="' . next_posts( $max_page, false ) . "\" $attr>" . preg_replace('/&([^#])(?![a-z]{1,8};)/i', '&#038;$1', $label) . '</a>';
 	}
 }
@@ -1506,8 +1509,8 @@
  * @param string $label Content for link text.
  * @param int $max_page Optional. Max pages.
  */
-function next_posts_link( $label = 'Next Page &raquo;', $max_page = 0 ) {
-	echo get_next_posts_link( $label, $max_page );
+function next_posts_link( $label = 'Next Page &raquo;', $max_page = 0, $class='' ) {
+	echo get_next_posts_link( $label, $max_page, $class );
 }
 
 /**
@@ -1556,11 +1559,14 @@
  * @param string $label Optional. Previous page link text.
  * @return string|null
  */
-function get_previous_posts_link( $label = '&laquo; Previous Page' ) {
+function get_previous_posts_link( $label = '&laquo; Previous Page', $class='' ) {
 	global $paged;
 
 	if ( !is_single() && $paged > 1 ) {
-		$attr = apply_filters( 'previous_posts_link_attributes', '' );
+		$attr = '';
+		if ( !empty($class) )
+			$attr = 'class="'. $class . '"';
+		$attr = apply_filters( 'previous_posts_link_attributes', $attr );
 		return '<a href="' . previous_posts( false ) . "\" $attr>". preg_replace( '/&([^#])(?![a-z]{1,8};)/', '&#038;$1', $label ) .'</a>';
 	}
 }
@@ -1573,8 +1579,8 @@
  *
  * @param string $label Optional. Previous page link text.
  */
-function previous_posts_link( $label = '&laquo; Previous Page' ) {
-	echo get_previous_posts_link( $label );
+function previous_posts_link( $label = '&laquo; Previous Page', $class='' ) {
+	echo get_previous_posts_link( $label, $class );
 }
 
 /**