Index: src/plugins/grass/qgsgrassmapcalc.cpp
===================================================================
--- src/plugins/grass/qgsgrassmapcalc.cpp	(revision 5998)
+++ src/plugins/grass/qgsgrassmapcalc.cpp	(working copy)
@@ -147,6 +147,7 @@
     mActionDeleteItem = new QAction( QIcon(myIconPath+"mapcalc_delete.png"), 
                         tr("Delete selected item"), this);
     mActionDeleteItem->setCheckable ( true );
+    mActionDeleteItem->setEnabled( false );
     ag->addAction ( mActionDeleteItem );
     tb->addAction ( mActionDeleteItem );
     connect ( mActionDeleteItem, SIGNAL(triggered()), this, SLOT(deleteItem()) );
@@ -798,6 +799,7 @@
 
     showOptions(mTool);
     setToolActionsOff(); 
+    mActionDeleteItem->setEnabled( false );
     mCanvas->update();
 }