diff --git a/src/meshlab/main.cpp b/src/meshlab/main.cpp
index ecf534faa..c9976d21e 100644
--- a/src/meshlab/main.cpp
+++ b/src/meshlab/main.cpp
@@ -23,6 +23,7 @@
 #include <common/mlapplication.h>
 #include <QMessageBox>
 #include "mainwindow.h"
+#include <QGLFormat>
 #include <QString>
 #include <clocale>
 
@@ -40,7 +41,11 @@ int main(int argc, char *argv[])
 
     QString tmp = MeshLabApplication::appArchitecturalName(MeshLabApplication::HW_ARCHITECTURE(QSysInfo::WordSize));
     QCoreApplication::setApplicationName(MeshLabApplication::appArchitecturalName(MeshLabApplication::HW_ARCHITECTURE(QSysInfo::WordSize)));
-   
+
+    QGLFormat fmt = QGLFormat::defaultFormat();
+    fmt.setAlphaBufferSize(8);
+    QGLFormat::setDefaultFormat(fmt);
+
     MainWindow window;
     window.showMaximized();
 
diff --git a/src/meshlabserver/mainserver.cpp b/src/meshlabserver/mainserver.cpp
index 37bbbb231..953cd5761 100644
--- a/src/meshlabserver/mainserver.cpp
+++ b/src/meshlabserver/mainserver.cpp
@@ -34,6 +34,7 @@
 #include "../meshlab/mainwindow.h"
 #include <clocale>
 
+#include <QGLFormat>
 #include <QFileInfo>
 
 
@@ -734,6 +735,10 @@ int main(int argc, char *argv[])
 	std::ptrdiff_t maxgpumem = (std::ptrdiff_t) gpumemmb * (float)(1024 * 1024);
 	vcg::QtThreadSafeMemoryInfo gpumeminfo(maxgpumem);
 
+    QGLFormat fmt = QGLFormat::defaultFormat();
+    fmt.setAlphaBufferSize(8);
+    QGLFormat::setDefaultFormat(fmt);
+
 	MeshDocument meshDocument;
 
 	MLSceneGLSharedDataContext shared(meshDocument, gpumeminfo, MeshLabScalarTest<MESHLAB_SCALAR>::doublePrecision(), 100000,100000);