--- calendar-2.03.2/Makefile.in.old	2013-09-14 16:15:43.760253519 +0100
+++ calendar-2.03.2/Makefile.in	2013-09-14 16:16:03.233279962 +0100
@@ -86,7 +86,7 @@
 
 CAMLIBS	= $(addprefix -I , $(DIRS))
 
-CAMLFLAGS= $(CAMLIBS)
+CAMLFLAGS= -g $(CAMLIBS)
 BYTEFLAGS= $(CAMLFLAGS)
 LINK_OPTFLAGS = $(CAMLFLAGS) -noassert
 OPTFLAGS = $(LINK_OPTFLAGS) -for-pack CalendarLib