fixed bug in org-babel-balanced-split when run on Emacs22

 Thanks to Martyn Jago for the test case

* lisp/ob.el (org-babel-balanced-split): Explicit checking if list
  before calling member.
* testing/lisp/test-ob.el (test-ob/org-babel-balanced-split): Testing
  the new Emacs22-proof behavior.

lisp/ob.el

@@ -1074,8 +1074,7 @@ ALTS is a cons of two character options where each option may be
 either the numeric code of a single character or a list of
 character alternatives.  For example to split on balanced
 instances of \"[ \t]:\" set ALTS to '((32 9) . 58)."
-  (flet ((matches (ch spec) (or (and (numberp spec) (= spec ch))
-				(member ch spec)))
+  (flet ((matches (ch spec) (if (listp spec) (member ch spec) (equal spec ch)))
 	 (matched (ch last)
 		  (if (consp alts)
 		      (and (matches ch (cdr alts))

testing/lisp/test-ob.el

@@ -583,6 +583,12 @@ on two lines
     (should (= 2 (length (org-babel-ref-split-args
 			  "a=\"this, no work\", b=1"))))))
 
+(ert-deftest test-ob/org-babel-balanced-split ()
+  (should (equal
+	   '(":a 1" "b [2 3]" "c (4 :d (5 6))")
+	   (org-babel-balanced-split ":a 1 :b [2 3] :c (4 :d (5 6))"
+				     '((32 9) . 58)))))
+
 (provide 'test-ob)
 
 ;;; test-ob ends here