--- a/configure
+++ b/configure
@@ -861,7 +861,7 @@ sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
 includedir='${prefix}/include'
-oldincludedir='/usr/include'
+oldincludedir='${prefix}/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
 infodir='${datarootdir}/info'
 htmldir='${docdir}'
@@ -6317,7 +6317,7 @@ $as_echo_n "checking for zlib... " >&6; 
 # Check whether --with-zlib was given.
 if test "${with_zlib+set}" = set; then
   withval=$with_zlib;  # check for header & func (in library) in given prefix
-	CPPFLAGS="${CPPFLAGS} -I${withval}/include"
+	CPPFLAGS="${CPPFLAGS}"
 	if test "x$staticzlib" = "xtrue"; then
 		LIBS="-Bstatic -L${withval} -lz -Bdynamic ${LIBS}"
 	else
@@ -10042,7 +10042,7 @@ _ACEOF
 if test "${with_libiconv+set}" = set; then
   withval=$with_libiconv;  # check for header & func (in library) in given prefix
 			if test "x$withval" != "x"; then
-				CPPFLAGS="${CPPFLAGS} -I${withval}/include"
+				CPPFLAGS="${CPPFLAGS}"
 				LIBS="-L${withval}/lib -liconv ${LIBS}"
 			else
 				LIBS="-liconv ${LIBS}"