diff --git a/helper/schema/resource_data.go b/helper/schema/resource_data.go
index 96aa088be..35107f3a4 100644
--- a/helper/schema/resource_data.go
+++ b/helper/schema/resource_data.go
@@ -79,7 +79,7 @@ func (d *ResourceData) Get(key string) interface{} {
 // set and the new value is. This is common, for example, for boolean
 // fields which have a zero value of false.
 func (d *ResourceData) GetChange(key string) (interface{}, interface{}) {
-	o, n := d.getChange(key, getSourceConfig, getSourceDiff)
+	o, n := d.getChange(key, getSourceState, getSourceDiff|getSourceExact)
 	return o.Value, n.Value
 }
 
@@ -105,6 +105,14 @@ func (d *ResourceData) getRaw(key string, level getSource) getResult {
 // HasChange returns whether or not the given key has been changed.
 func (d *ResourceData) HasChange(key string) bool {
 	o, n := d.GetChange(key)
+
+	// There is a special case needed for *schema.Set's as they contain
+	// a function and reflect.DeepEqual will only say two functions are
+	// equal when they are both nil (which in this case they are not).
+	if reflect.TypeOf(o).String() == "*schema.Set" {
+		return !reflect.DeepEqual(o.(*Set).m, n.(*Set).m)
+	}
+
 	return !reflect.DeepEqual(o, n)
 }
 
diff --git a/helper/schema/resource_data_test.go b/helper/schema/resource_data_test.go
index fa0c18ca9..618973cde 100644
--- a/helper/schema/resource_data_test.go
+++ b/helper/schema/resource_data_test.go
@@ -1000,6 +1000,37 @@ func TestResourceDataHasChange(t *testing.T) {
 
 			Change: true,
 		},
+
+		{
+			Schema: map[string]*Schema{
+				"ports": &Schema{
+					Type:     TypeSet,
+					Optional: true,
+					Elem:     &Schema{Type: TypeInt},
+					Set:      func(a interface{}) int { return a.(int) },
+				},
+			},
+
+			State: &terraform.InstanceState{
+				Attributes: map[string]string{
+					"ports.#":  "1",
+					"ports.80": "80",
+				},
+			},
+
+			Diff: &terraform.InstanceDiff{
+				Attributes: map[string]*terraform.ResourceAttrDiff{
+					"ports.#": &terraform.ResourceAttrDiff{
+						Old: "1",
+						New: "0",
+					},
+				},
+			},
+
+			Key: "ports",
+
+			Change: true,
+		},
 	}
 
 	for i, tc := range cases {