diff --git a/tests/Makefile.am b/tests/Makefile.am
index dfb96b0..336794f 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -1,76 +1,76 @@
 # Makefile.am - Makefile for GpgOL tests.
 # Copyright (C) 2016 Bundesamt für Sicherheit in der Informationstechnik
 # Software engineering by Intevation GmbH
 #
 # This file is part of GPGOL.
 #
 # GpgOL is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
 # License as published by the Free Software Foundation; either
 # version 2.1 of the License, or (at your option) any later version.
 #
 # GpgOL is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU Lesser General Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public License
 # along with this program; if not, see <http://www.gnu.org/licenses/>.
 
 ## Process this file with automake to produce Makefile.in
 
 GPG = gpg
 
 if HAVE_W32_SYSTEM
 TESTS = t-parser
 endif
 
 AM_LDFLAGS = @GPGME_LIBS@ -lgpgmepp
 
 AM_CFLAGS = -I$(top_srcdir)/src $(GPGME_CFLAGS) $(LIBASSUAN_CFLAGS) -DBUILD_TESTS
 if !HAVE_W32_SYSTEM
 AM_CXXFLAGS = -I$(top_srcdir)/src $(GPGME_CFLAGS) $(GPGME_CFLAGS)/gpgme++ \
 			  $(LIBASSUAN_CFLAGS) -std=c++11  -D_FILE_OFFSET_BITS=64 \
 			  -DBUILD_TESTS -DDATADIR=\"$(abs_srcdir)/data\" \
-              -DGPGHOMEDIR=\"$(abs_srcdir)/gnupg_home\"
+              -DGPGHOMEDIR=\"$(abs_srcdir)/gnupg_home\" $(GPGMEPP_CXXFLAGS)
 else
 AM_CXXFLAGS = -I$(top_srcdir)/src $(GPGME_CFLAGS) $(GPGME_CFLAGS)/gpgme++ \
-			  $(LIBASSUAN_CFLAGS) -std=c++11  -D_FILE_OFFSET_BITS=64 \
-			  -DBUILD_TESTS
+			  $(LIBASSUAN_CFLAGS) $(GPGMEPP_CXXFLAGS) -std=c++11 \
+			  -D_FILE_OFFSET_BITS=64 -DBUILD_TESTS
 endif
 LDADD = @GPG_ERROR_LIBS@
 
 
 if HAVE_W32_SYSTEM
 run_parser_LDADD =  \
 	-L ../src -lgpgmepp -lgpgme -lassuan -lgpg-error \
 	-lmapi32 -lshell32 -lgdi32 -lcomdlg32 \
 	-lole32 -loleaut32 -lws2_32 -ladvapi32 \
 	-luuid -lgdiplus -lrpcrt4
 endif
 
 parser_SRC= ../src/parsecontroller.cpp \
 			../src/parsecontroller.h \
 			../src/attachment.cpp ../src/attachment.h \
 			../src/mimedataprovider.h ../src/mimedataprovider.cpp \
 			../src/rfc822parse.c ../src/rfc822parse.h \
 			../src/rfc2047parse.c ../src/rfc2047parse.h \
 			../src/common_indep.c ../src/common_indep.h \
 			../src/debug.cpp ../src/debug.h \
 			../src/memdbg.cpp ../src/memdbg.h \
 			../src/cpphelp.cpp ../src/cpphelp.h \
 			../src/xmalloc.h
 
 if !HAVE_W32_SYSTEM
 t_parser_SOURCES = t-parser.cpp $(parser_SRC)
 run_parser_SOURCES = run-parser.cpp $(parser_SRC)
 else
 run_parser_SOURCES = run-parser.cpp $(parser_SRC) \
 			../src/w32-gettext.cpp ../src/w32-gettext.h
 endif
 
 if !HAVE_W32_SYSTEM
 noinst_PROGRAMS = t-parser run-parser
 else
 noinst_PROGRAMS = run-parser
 endif