wxGUI: fix raising error

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@52945 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/gui_core/forms.py

@@ -2047,7 +2047,7 @@ class GUI:
             self.grass_task = gtask.parse_interface(gcmd.GetRealCmd(cmd[0]),
                                                     blackList = _blackList)
         except (grass.ScriptError, ValueError), e:
-            raise gcmd.GException(e)
+            raise gcmd.GException(e.value)
         
         # if layer parameters previously set, re-insert them into dialog
         if completed is not None: