diff --git a/configure.ac b/configure.ac
index 6ee09aa..d9a5baa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -110,6 +110,7 @@ AC_CHECK_HEADER([pkcs11.h], [], [AC_MSG_ERROR([Header pkcs11.h is required])])
 AC_CHECK_HEADER([wintypes.h], [], [AC_MSG_ERROR([Header wintypes.h is required])])
 AC_CHECK_HEADER([mrw/checkcxx11.hxx], [], [AC_MSG_ERROR([please install mrw-c++])])
 AX_CXX_CHECK_QT([QTGUI], [QtCore QtGui])
+AX_CXX_CHECK_QT([QTWIDGETS], [QtWidgets]) # optional, needed only for qt5
 AX_CXX_CHECK_QT([QTNETWORK], [QtNetwork])
 
 AC_ARG_ENABLE(pedantic,