--- Makefile.in.orig	2012-11-04 18:15:35.000000000 +0700
+++ Makefile.in	2012-11-04 18:15:45.000000000 +0700
@@ -956,7 +956,7 @@
 
 # Create HTML docs
 doc:
-@SPHINX_BUILD_TRUE@	cd $(top_srcdir)/docs/en_US && make -f Makefile.sphinx SPHINXBUILD=${SPHINX_BUILD} htmlhelp
+@SPHINX_BUILD_TRUE@	cd $(top_srcdir)/docs/en_US && ${MAKE} -f Makefile.sphinx SPHINXBUILD=${SPHINX_BUILD} htmlhelp
 
 all: doc