Generate only if docbook is installed

configure.in

@@ -13,6 +13,8 @@ AM_PROG_CC_C_O
 AC_GNU_SOURCE
 AC_PROG_LIBTOOL
 AC_CHECK_PROG(SETCAP, setcap, yes, no)
+AC_CHECK_PROG(DOCBOOK, docbook2man, yes, no)
+AM_CONDITIONAL(ENABLE_DOCBOOK, test x$DOCBOOK = xyes)
 
 AC_CHECK_HEADERS([linux/netlink.h linux/genetlink.h], [], AC_MSG_ERROR([netlink headers not found]),
 [#include <linux/types.h>
@@ -72,6 +74,17 @@ AC_CONFIG_FILES([
 AC_CONFIG_COMMANDS([default],[[]],[[]])
 AC_OUTPUT
 
+if test "x$DOCBOOK" = "xno"; then
+   AC_MSG_NOTICE([ 
+
+Warning:
+--------
+The docbook tool is not installed, the man pages won't be generated.
+
+])
+
+fi
+
 if test "x$SETCAP" = "xno"; then
    AC_MSG_NOTICE([ 
 

doc/Makefile.am

+if ENABLE_DOCBOOK
+man_MANS = \
+	lxc-create.1 \
+	lxc-destroy.1 \
+	lxc-execute.1 \
+	lxc-start.1 \
+	lxc-stop.1 \
+	lxc-freeze.1 \
+	lxc-unfreeze.1 \
+	lxc-monitor.1 \
+	lxc-wait.1 \
+	lxc-ls.1 \
+	lxc-ps.1
+
+
+%.1 : %.sgml 
+	docbook2man $<
+endif
\ No newline at end of file