1 files changed, 5 insertions, 0 deletions
diff --git a/PySide/QtGui/glue/qapplication_init.cpp b/PySide/QtGui/glue/qapplication_init.cpp
index 265db256b..469e18c99 100644
--- a/PySide/QtGui/glue/qapplication_init.cpp
+++ b/PySide/QtGui/glue/qapplication_init.cpp
@@ -3,6 +3,11 @@ extern PyObject* moduleQtGui;
 
 int SbkQApplication_Init(PyObject* self, PyObject* args, PyObject*)
 {
+    if (QApplication::instance()) {
+        PyErr_SetString(PyExc_RuntimeError, "A QApplication instance already exists.");
+        return -1;
+    }
+
     int numArgs = PyTuple_GET_SIZE(args);
     if (numArgs != 1) {
         PyErr_BadArgument();