Index: rewrite.php
===================================================================
--- rewrite.php	(revision 10258)
+++ rewrite.php	(working copy)
@@ -826,6 +826,20 @@
 		$rewrite_rules = array();
 		$page_structure = $this->get_page_permastruct();
 
+		//support for static posts page with custom permalink
+		//no need to check if rewrite not enabled
+		if (get_option('show_on_front') && !$this->using_index_permalinks()) {			
+			$id = get_option('page_for_posts');
+			if (!empty($id)) {
+				//get the page
+				$page = get_page($id);
+			
+				// use post_name for matching
+				if (0 === strpos(ltrim($this->permalink_structure, '/'), $page->post_name))
+					$this->use_verbose_page_rules = true;	
+			}
+		}
+
 		if ( ! $this->use_verbose_page_rules ) {
 			$this->add_rewrite_tag('%pagename%', "(.+?)", 'pagename=');
 			$rewrite_rules = array_merge($rewrite_rules, $this->generate_rewrite_rules($page_structure, EP_PAGES));