diff --git a/Makefile b/Makefile
index 0b15abe41..e6bdfbef8 100644
--- a/Makefile
+++ b/Makefile
@@ -125,6 +125,7 @@ LISPF      = 	org.el			\
 		ob-eval.el		\
 		ob-keys.el		\
 		ob-C.el			\
+		ob-calc.el		\
 		ob-ditaa.el		\
 		ob-haskell.el		\
 		ob-perl.el		\
diff --git a/contrib/babel/library-of-babel.org b/contrib/babel/library-of-babel.org
index 07c40aa9c..abc15a91f 100644
--- a/contrib/babel/library-of-babel.org
+++ b/contrib/babel/library-of-babel.org
@@ -286,11 +286,85 @@ are optional.
 #+begin_src python
 a
 #+end_src
-
 #+srcname: python-add(a=1, b=2)
 #+begin_src python
 a + b
 #+end_src
+* GANTT Charts
 
-
-
+The =elispgantt= source block was sent to the mailing list by Eric
+Fraga.  It was modified slightly by Tom Dye.
+ 
+#+source: elispgantt
+#+begin_src emacs-lisp :var table=gantttest
+  (let ((dates "")
+        (entries (nthcdr 2 table))
+        (milestones "")
+        (nmilestones 0)
+        (ntasks 0)
+        (projecttime 0)
+        (tasks "")
+        (xlength 1))
+    (message "Initial: %s\n" table)
+    (message "Entries: %s\n" entries)
+    (while entries
+      (let ((entry (first entries)))
+        (if (listp entry)
+            (let ((id (first entry))
+                  (type (nth 1 entry))
+                  (label (nth 2 entry))
+                  (task (nth 3 entry))
+                  (dependencies (nth 4 entry))
+                  (start (nth 5 entry))
+                  (duration (nth 6 entry))
+                  (end (nth 7 entry))
+                  (alignment (nth 8 entry)))
+              (if (> start projecttime) (setq projecttime start))
+              (if (string= type "task")
+                  (let ((end (+ start duration))
+                        (textposition (+ start (/ duration 2)))
+                        (flush ""))
+                    (if (string= alignment "left")
+                        (progn
+                          (setq textposition start)
+                          (setq flush "[left]"))
+                      (if (string= alignment "right")
+                          (progn
+                            (setq textposition end)
+                            (setq flush "[right]"))))
+                    (setq tasks
+                          (format "%s  \\gantttask{%s}{%s}{%d}{%d}{%d}{%s}\n"
+                                  tasks label task start end textposition flush))
+                    (setq ntasks (+ 1 ntasks))
+                    (if (> end projecttime)
+                        (setq projecttime end)))
+                (if (string= type "milestone")
+                    (progn
+                      (setq milestones
+                            (format
+                             "%s  \\ganttmilestone{$\\begin{array}{c}\\mbox{%s}\\\\ \\mbox{%s}\\end{array}$}{%d}\n"
+                             milestones label task start))
+                      (setq nmilestones (+ 1 nmilestones)))
+                  (if (string= type "date")
+                      (setq dates (format "%s  \\ganttdateline{%s}{%d}\n"
+                                          dates label start))
+                    (message "Ignoring entry with type %s\n" type)))))
+          (message "Ignoring non-list entry %s\n" entry)) ; end if list entry
+        (setq entries (cdr entries))))  ; end while entries left
+    (format "\\pgfdeclarelayer{background}
+  \\pgfdeclarelayer{foreground}
+  \\pgfsetlayers{background,foreground}
+  \\renewcommand{\\ganttprojecttime}{%d}
+  \\renewcommand{\\ganttntasks}{%d}
+  \\noindent
+  \\begin{tikzpicture}[y=-0.75cm,x=0.75\\textwidth]
+    \\begin{pgfonlayer}{background}
+      \\draw[very thin, red!10!white] (0,1+\\ganttntasks) grid [ystep=0.75cm,xstep=1/\\ganttprojecttime] (1,0);
+      \\draw[\\ganttdatelinecolour] (0,0) -- (1,0);
+      \\draw[\\ganttdatelinecolour] (0,1+\\ganttntasks) -- (1,1+\\ganttntasks);
+    \\end{pgfonlayer}
+  %s
+  %s
+  %s
+  \\end{tikzpicture}" projecttime ntasks tasks milestones dates))
+#+end_src
diff --git a/lisp/ob-calc.el b/lisp/ob-calc.el
index eb6d970c3..79fe40408 100644
--- a/lisp/ob-calc.el
+++ b/lisp/ob-calc.el
@@ -40,6 +40,8 @@
 
 (defun org-babel-execute:calc (body params)
   "Execute a block of calc code with Babel."
+  (unless (get-buffer "*Calculator*")
+    (save-window-excursion (calc) (calc-quit)))
   (let* ((vars (mapcar #'cdr (org-babel-get-header params :var)))
 	 (var-syms (mapcar #'car vars))
 	 (var-names (mapcar #'symbol-name var-syms)))
@@ -48,7 +50,7 @@
        (calc-push-list (list (cdr pair)))
        (calc-store-into (car pair)))
      vars)
-    (mapcar
+    (mapc
      (lambda (line)
        (when (> (length line) 0)
 	 (cond
@@ -80,13 +82,13 @@
 					     (calc-pop 1)))
 				       el))
 				   ;; parse line into calc objects
-				   (first (math-read-exprs line))))))))
+				   (car (math-read-exprs line))))))))
 		   (calc-eval line))))))))
      (mapcar #'org-babel-trim
 	     (split-string (org-babel-expand-body:calc body params) "[\n\r]"))))
   (save-excursion
-    (set-buffer (get-buffer "*Calculator*"))
-    (calc-eval (calc-top 1))))
+    (with-current-buffer (get-buffer "*Calculator*")
+      (calc-eval (calc-top 1)))))
 
 (provide 'ob-calc)
 
diff --git a/lisp/ob-lisp.el b/lisp/ob-lisp.el
index f550a54e1..1089e4c6b 100644
--- a/lisp/ob-lisp.el
+++ b/lisp/ob-lisp.el
@@ -41,13 +41,18 @@
 (require 'ob-ref)
 (require 'ob-comint)
 (require 'ob-eval)
-(require 'slime)
+
+(declare-function slime-eval "ext:slime" (sexp &optional package))
+(declare-function slime-process "ext:slime" (&optional connection))
+(declare-function slime-connected-p "ext:slime" ())
 
 (defvar org-babel-default-header-args:lisp '()
   "Default header arguments for lisp code blocks.")
 
 (defcustom org-babel-lisp-cmd "sbcl --script"
-  "Name of command used to evaluate lisp blocks.")
+  "Name of command used to evaluate lisp blocks."
+  :group 'org-babel
+  :type 'string)
 
 (defun org-babel-expand-body:lisp (body params)
   "Expand BODY according to PARAMS, return the expanded body."
@@ -63,6 +68,7 @@
 (defun org-babel-execute:lisp (body params)
   "Execute a block of Lisp code with org-babel.
 This function is called by `org-babel-execute-src-block'"
+  (require 'slime)
   (message "executing Lisp source code block")
   (let* ((session (org-babel-lisp-initiate-session
 		   (cdr (assoc :session params))))
@@ -94,6 +100,7 @@ This function is called by `org-babel-execute-src-block'"
 (defun org-babel-lisp-initiate-session (&optional session)
   "If there is not a current inferior-process-buffer in SESSION
 then create.  Return the initialized session."
+  (require 'slime)
   (unless (string= session "none")
     (save-window-excursion
       (or (slime-connected-p)
diff --git a/lisp/org-exp-blocks.el b/lisp/org-exp-blocks.el
index 3751e68e0..a469afcac 100644
--- a/lisp/org-exp-blocks.el
+++ b/lisp/org-exp-blocks.el
@@ -201,9 +201,6 @@ which defaults to the value of `org-export-blocks-witheld'."
 	(interblock start (point-max))
 	(run-hooks 'org-export-blocks-postblock-hook)))))
 
-(add-hook 'org-export-preprocess-after-include-files-hook
-	  'org-export-blocks-preprocess)
-
 ;;================================================================================
 ;; type specific functions
 
diff --git a/lisp/org-exp.el b/lisp/org-exp.el
index 05d8ef676..2affcba2f 100644
--- a/lisp/org-exp.el
+++ b/lisp/org-exp.el
@@ -1080,6 +1080,9 @@ on this string to produce the exported version."
       ;; Mark end of lists
       (org-export-mark-list-ending backend)
 
+      ;; Export code blocks
+      (org-export-blocks-preprocess)
+
       ;; Handle source code snippets
       (org-export-replace-src-segments-and-examples backend)