diff --git a/acinclude.m4 b/acinclude.m4
index 1e0a391..456d14e 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -1836,7 +1836,7 @@ else
  all_includes="$KDE_INCLUDES $all_includes"
 fi
 
-KDE_DEFAULT_CXXFLAGS="-DQT_CLEAN_NAMESPACE -DQT_NO_ASCII_CAST -DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION"
+KDE_DEFAULT_CXXFLAGS="-DQT_NO_ASCII_CAST -DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION"
  
 KDE_LDFLAGS="-L$kde_libraries"
 if test ! "$kde_libraries" = "$x_libraries" && test ! "$kde_libraries" = "$qt_libraries" ; then 
diff --git a/aclocal.m4 b/aclocal.m4
index 2784727..084c281 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1848,7 +1848,7 @@ else
  all_includes="$KDE_INCLUDES $all_includes"
 fi
 
-KDE_DEFAULT_CXXFLAGS="-DQT_CLEAN_NAMESPACE -DQT_NO_ASCII_CAST -DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION"
+KDE_DEFAULT_CXXFLAGS="-DQT_NO_ASCII_CAST -DQT_NO_STL -DQT_NO_COMPAT -DQT_NO_TRANSLATION"
  
 KDE_LDFLAGS="-L$kde_libraries"
 if test ! "$kde_libraries" = "$x_libraries" && test ! "$kde_libraries" = "$qt_libraries" ; then