diff --git a/SolidityNameAndTypeResolution.cpp b/SolidityNameAndTypeResolution.cpp
index 591cf053a..3bec70a2b 100644
--- a/SolidityNameAndTypeResolution.cpp
+++ b/SolidityNameAndTypeResolution.cpp
@@ -28,6 +28,7 @@
 #include <libsolidity/Parser.h>
 #include <libsolidity/NameAndTypeResolver.h>
 #include <libsolidity/Exceptions.h>
+#include <libsolidity/GlobalContext.h>
 #include "TestHelper.h"
 
 using namespace std;
@@ -48,16 +49,28 @@ ASTPointer<SourceUnit> parseTextAndResolveNames(std::string const& _source)
 	ASTPointer<SourceUnit> sourceUnit = parser.parse(std::make_shared<Scanner>(CharStream(_source)));
 	NameAndTypeResolver resolver({});
 	resolver.registerDeclarations(*sourceUnit);
+	std::shared_ptr<GlobalContext> globalContext = make_shared<GlobalContext>();
+
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			globalContext->setCurrentContract(*contract);
+			resolver.updateDeclaration(*globalContext->getCurrentThis());
+			resolver.updateDeclaration(*globalContext->getCurrentSuper());
 			resolver.resolveNamesAndTypes(*contract);
+		}
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			globalContext->setCurrentContract(*contract);
+			resolver.updateDeclaration(*globalContext->getCurrentThis());
 			resolver.checkTypeRequirements(*contract);
+		}
 
 	return sourceUnit;
 }
 
+
 static ContractDefinition const* retrieveContract(ASTPointer<SourceUnit> _source, unsigned index)
 {
 	ContractDefinition* contract;
@@ -359,7 +372,7 @@ BOOST_AUTO_TEST_CASE(function_canonical_signature)
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
 		{
 			auto functions = contract->getDefinedFunctions();
-			BOOST_CHECK_EQUAL("foo(uint256,uint64,bool)", functions[0]->getCanonicalSignature());
+			BOOST_CHECK_EQUAL("foo(uint256,uint64,bool)", functions[0]->externalSignature());
 		}
 }
 
@@ -376,10 +389,95 @@ BOOST_AUTO_TEST_CASE(function_canonical_signature_type_aliases)
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
 		{
 			auto functions = contract->getDefinedFunctions();
-			BOOST_CHECK_EQUAL("boo(uint256,bytes32,address)", functions[0]->getCanonicalSignature());
+			if (functions.empty())
+				continue;
+			BOOST_CHECK_EQUAL("boo(uint256,bytes32,address)", functions[0]->externalSignature());
 		}
 }
 
+BOOST_AUTO_TEST_CASE(function_external_types)
+{
+	ASTPointer<SourceUnit> sourceUnit;
+	char const* text = R"(
+		contract C {
+			uint a;
+		}
+		contract Test {
+			function boo(uint arg2, bool arg3, bytes8 arg4, bool[2] pairs, uint[] dynamic, C carg) external returns (uint ret) {
+			   ret = 5;
+			}
+		})";
+	ETH_TEST_REQUIRE_NO_THROW(sourceUnit = parseTextAndResolveNames(text), "Parsing and name Resolving failed");
+	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			auto functions = contract->getDefinedFunctions();
+			if (functions.empty())
+				continue;
+			BOOST_CHECK_EQUAL("boo(uint256,bool,bytes8,bool[2],uint256[],address)", functions[0]->externalSignature());
+		}
+}
+
+BOOST_AUTO_TEST_CASE(function_external_call_allowed_conversion)
+{
+	char const* text = R"(
+		contract C {}
+		contract Test {
+			function externalCall()	{
+				C arg;
+				this.g(arg);
+			}
+			function g (C c) external {}
+	})";
+	BOOST_CHECK_NO_THROW(parseTextAndResolveNames(text));
+}
+
+BOOST_AUTO_TEST_CASE(function_external_call_not_allowed_conversion)
+{
+	char const* text = R"(
+		contract C {}
+		contract Test {
+			function externalCall()	{
+				address arg;
+				this.g(arg);
+			}
+			function g (C c) external {}
+	})";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
+}
+
+BOOST_AUTO_TEST_CASE(function_internal_allowed_conversion)
+{
+	char const* text = R"(
+		contract C {
+			uint a;
+		}
+		contract Test {
+			C a;
+			function g (C c) {}
+			function internalCall() {
+				g(a);
+			}
+	})";
+	BOOST_CHECK_NO_THROW(parseTextAndResolveNames(text));
+}
+
+BOOST_AUTO_TEST_CASE(function_internal_not_allowed_conversion)
+{
+	char const* text = R"(
+		contract C {
+			uint a;
+		}
+		contract Test {
+			address a;
+			function g (C c) {}
+			function internalCall() {
+				g(a);
+			}
+	})";
+	BOOST_CHECK_THROW(parseTextAndResolveNames(text), TypeError);
+}
+
 BOOST_AUTO_TEST_CASE(hash_collision_in_interface)
 {
 	char const* text = "contract test {\n"