Make sure tags matching is case-insensitive.

lisp/ChangeLog

@@ -1,3 +1,10 @@
+2008-09-19  Carsten Dominik  <dominik@science.uva.nl>
+
+	* org.el (org-scan-tags): Make sure that tags matching is not case
+	sensitive.  TODO keyword matching is case sensitive, however, to
+	avoid confusion with similar words that are not meant to be
+	keywords.
+
 2008-09-18  Carsten Dominik  <dominik@science.uva.nl>
 
 	* org.el (org-get-local-tags-at): New function.

lisp/org.el

@@ -9456,7 +9456,7 @@ only lines with a TODO keyword are included in the output."
 	    (setcdr (car tags-alist)
 		    (org-remove-uniherited-tags (cdar tags-alist))))
 	  (when (and (or (not todo-only) (member todo org-not-done-keywords))
-		     (eval matcher)
+		     (let ((case-fold-search t)) (eval matcher))
 		     (or
 		      (not (member org-archive-tag tags-list))
 		      ;; we have an archive tag, should we use this anyway?