--- a/configure.ac
+++ b/configure.ac
@@ -54,13 +54,10 @@
 
 # check Doxygen
 DOXYGEN=""
-AC_ARG_WITH(doxygen, [  --with-doxygen    Generate doxygen documentation ],
-[AC_CHECK_PROG(DOX, doxygen, yes)
-if test "x$DOX" != x ; then
-	DOXYGEN="doxygen"
-else
-	AC_MSG_ERROR([*** Doxygen not found])
-fi
+AC_ARG_WITH(doxygen, [  --with-doxygen    Generate doxygen documentation ])
+AS_IF([test "x$with_doxygen" = "xyes"], [
+  AC_CHECK_PROG(DOX, doxygen, yes)
+  DOXYGEN="doxygen"
 ])
 AC_SUBST(DOXYGEN)
 AM_CONDITIONAL(HAVE_DOXYGEN, test x$DOXYGEN != x)
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -19,5 +19,4 @@
 
 
 # install
-docdir = $(datadir)/doc/@PACKAGE@-@VERSION@/html
-doc_DATA = $(shell find $(top_srcdir)/docs/html -name \*.*) 
+html_DATA = $(shell find $(top_srcdir)/docs/html -name \*.*)