Link against system libical instead of bundled.
https://bugzilla.redhat.com/show_bug.cgi?id=459923

Lubomir Rintel <lkundrak@v3.sk>

--- calendar/base/build/Makefile.in.libical	2007-12-27 11:01:41.000000000 +0100
+++ calendar/base/build/Makefile.in	2008-09-23 16:02:42.000000000 +0200
@@ -63,7 +63,6 @@
 	js \
 	xpconnect \
 	string \
-	ical \
 	calbase
 
 CPPSRCS = calBaseModule.cpp \
@@ -74,7 +73,6 @@
 
 SHARED_LIBRARY_LIBS = \
     $(DEPTH)/calendar/base/src/$(LIB_PREFIX)calbase_s.$(LIB_SUFFIX) \
-    $(DEPTH)/calendar/libical/src/libical/$(LIB_PREFIX)mozical.$(LIB_SUFFIX) \
     $(NULL)
 
 ifdef MOZILLA_INTERNAL_API
@@ -94,4 +92,7 @@
 	$(NULL)
 endif
 
+# External libical
+EXTRA_DSO_LDOPTS += -lical
+
 include $(topsrcdir)/config/rules.mk
--- calendar/Makefile.in.libical	2008-09-23 17:13:34.000000000 +0200
+++ calendar/Makefile.in	2008-09-23 17:07:30.000000000 +0200
@@ -42,7 +42,7 @@
 include $(DEPTH)/config/autoconf.mk
 
 MODULE	= calendar
-DIRS = libical resources base providers import-export locales
+DIRS = resources base providers import-export locales
 
 ifdef ENABLE_TESTS
 DIRS += test
--- calendar/lightning/Makefile.in.libical	2008-07-24 03:07:05.000000000 +0200
+++ calendar/lightning/Makefile.in	2008-09-23 16:02:42.000000000 +0200
@@ -71,7 +71,7 @@
 endif
 endif
 
-DIRS = ../libical \
+DIRS = \
        ../locales \
        ../base \
        ../providers \
--- /dev/null	2008-09-23 20:44:22.879046487 +0200
+++ calendar/base/src/ical.h	2008-09-24 11:28:09.000000000 +0200
@@ -0,0 +1,3 @@
+#pragma GCC visibility push(default)
+#include <libical/ical.h>
+#pragma GCC visibility pop