Index: vala/valaforeachstatement.vala
===================================================================
--- vala/valaforeachstatement.vala	(revision 602)
+++ vala/valaforeachstatement.vala	(working copy)
@@ -49,8 +49,13 @@
 			_collection.parent_node = this;
 		}
 	}
-	
+
 	/**
+	 * Specifies the method that returns the iterator 
+	 */
+	public Method! iterator_method { get; set; }
+
+	/**
 	 * Specifies the loop body.
 	 */
 	public Block body {
Index: vala/valasemanticanalyzer.vala
===================================================================
--- vala/valasemanticanalyzer.vala	(revision 602)
+++ vala/valasemanticanalyzer.vala	(working copy)
@@ -886,15 +886,20 @@
 		stmt.collection_variable_declarator.active = true;
 
 		var collection_type = stmt.collection.static_type.data_type;
-		if (iterable_type != null && collection_type.is_subtype_of (iterable_type)) {
+
+		TypeReference iter_as_reference = new TypeReference ();
+		iter_as_reference.data_type = iterator_type;
+		Method m = symbol_lookup_inherited (collection_type, "get_iterator") as Method;
+
+		if (m != null && is_type_compatible (m.return_type, iter_as_reference) && m.get_parameters().size == 0) {
 			stmt.iterator_variable_declarator = new VariableDeclarator ("%s_it".printf (stmt.variable_name));
 			stmt.iterator_variable_declarator.type_reference = new TypeReference ();
 			stmt.iterator_variable_declarator.type_reference.data_type = iterator_type;
 			stmt.iterator_variable_declarator.type_reference.takes_ownership = true;
 			stmt.iterator_variable_declarator.type_reference.add_type_argument (stmt.type_reference);
-
 			stmt.add_local_variable (stmt.iterator_variable_declarator);
 			stmt.iterator_variable_declarator.active = true;
+			stmt.iterator_method = m;
 		} else if (!(collection_type is Array || collection_type == glist_type || collection_type == gslist_type)) {
 			stmt.error = true;
 			Report.error (stmt.source_reference, "Collection not iterable");
Index: gobject/valacodegenerator.vala
===================================================================
--- gobject/valacodegenerator.vala	(revision 602)
+++ gobject/valacodegenerator.vala	(working copy)
@@ -1635,13 +1635,13 @@
 
 			cfor.add_iterator (new CCodeAssignment (new CCodeIdentifier (it_name), new CCodeMemberAccess.pointer (new CCodeIdentifier (it_name), "next")));
 			cblock.add_statement (cfor);
-		} else if (stmt.collection.static_type.data_type.is_subtype_of (iterable_type)) {
+		} else if (stmt.iterator_method != null) {
 			var it_name = "%s_it".printf (stmt.variable_name);
 
 			var citdecl = new CCodeDeclaration (iterator_type.get_cname () + "*");
-			var it_method = (Method) iterable_type.scope.lookup ("iterator");
+			var it_method = stmt.iterator_method;
 			var it_ccall = new CCodeFunctionCall (new CCodeIdentifier (it_method.get_cname ()));
-			it_ccall.add_argument (new InstanceCast (new CCodeIdentifier (collection_backup.name), iterable_type));
+			it_ccall.add_argument (new InstanceCast (new CCodeIdentifier (collection_backup.name), (DataType ) it_method.parent_symbol));
 			var citvardecl = new CCodeVariableDeclarator.with_initializer (it_name, it_ccall);
 			citvardecl.line = cblock.line;
 			citdecl.add_declarator (citvardecl);