diff --git a/src/utility/url.cpp b/src/utility/url.cpp
index d3c5445d..f9157d64 100644
--- a/src/utility/url.cpp
+++ b/src/utility/url.cpp
@@ -130,26 +130,23 @@ const string url::build() const
 		oss << urlUtils::encode(m_path);
 	}
 
-	const std::vector <ref <const propertySet::property> > params
-		= m_params.getPropertyList();
 
-	if (!params.empty())
+	if (!m_params.empty())
 	{
 		if (m_path.empty())
 			oss << "/";
 
 		oss << "?";
 
-		for (unsigned int i = 0 ; i < params.size() ; ++i)
+		for (std::map <string, string>::const_iterator it = m_params.begin() ;
+		     it != m_params.end() ; ++it)
 		{
-			const ref <const propertySet::property> prop = params[i];
-
-			if (i != 0)
+			if (it != m_params.begin())
 				oss << "&";
 
-			oss << urlUtils::encode(prop->getName());
+			oss << urlUtils::encode((*it).first);
 			oss << "=";
-			oss << urlUtils::encode(prop->getValue <string>());
+			oss << urlUtils::encode((*it).second);
 		}
 	}
 
@@ -267,7 +264,7 @@ void url::parse(const string& str)
 		portNum = UNSPECIFIED_PORT;
 
 	// Extract parameters
-	m_params.removeAllProperties();
+	m_params.clear();
 
 	if (!params.empty())
 	{
@@ -300,7 +297,7 @@ void url::parse(const string& str)
 			name = urlUtils::decode(name);
 			value = urlUtils::decode(value);
 
-			m_params.setProperty(name, value);
+			m_params[name] = value;
 
 			if (pos != string::npos)
 				++pos;
@@ -393,13 +390,13 @@ void url::setPath(const string& path)
 }
 
 
-const propertySet& url::getParams() const
+const std::map <string, string>& url::getParams() const
 {
 	return (m_params);
 }
 
 
-propertySet& url::getParams()
+std::map <string, string>& url::getParams()
 {
 	return (m_params);
 }
diff --git a/tests/utility/urlTest.cpp b/tests/utility/urlTest.cpp
index 6703ecd3..85991511 100644
--- a/tests/utility/urlTest.cpp
+++ b/tests/utility/urlTest.cpp
@@ -164,29 +164,29 @@ VMIME_TEST_SUITE_BEGIN(urlTest)
 		vmime::utility::url u1("", "");
 
 		VASSERT_EQ("1.1", true, parseHelper(u1, "proto://host/path?p1=v1&p2=v2"));
-		VASSERT_EQ("1.2", "v1", u1.getParams().getProperty <vmime::string>("p1"));
-		VASSERT_EQ("1.3", "v2", u1.getParams().getProperty <vmime::string>("p2"));
+		VASSERT_EQ("1.2", "v1", u1.getParams()["p1"]);
+		VASSERT_EQ("1.3", "v2", u1.getParams()["p2"]);
 		VASSERT_EQ("1.4", "/path", u1.getPath());
 
 		vmime::utility::url u2("", "");
 
 		VASSERT_EQ("2.1", true, parseHelper(u2, "proto://host/path?p1=v1&p2"));
-		VASSERT_EQ("2.2", "v1", u2.getParams().getProperty <vmime::string>("p1"));
-		VASSERT_EQ("2.3", "p2", u2.getParams().getProperty <vmime::string>("p2"));
+		VASSERT_EQ("2.2", "v1", u2.getParams()["p1"]);
+		VASSERT_EQ("2.3", "p2", u2.getParams()["p2"]);
 		VASSERT_EQ("2.4", "/path", u2.getPath());
 
 		vmime::utility::url u3("", "");
 
 		VASSERT_EQ("3.1", true, parseHelper(u3, "proto://host/?p1=v1&p2=v2"));
-		VASSERT_EQ("3.2", "v1", u3.getParams().getProperty <vmime::string>("p1"));
-		VASSERT_EQ("3.3", "v2", u3.getParams().getProperty <vmime::string>("p2"));
+		VASSERT_EQ("3.2", "v1", u3.getParams()["p1"]);
+		VASSERT_EQ("3.3", "v2", u3.getParams()["p2"]);
 		VASSERT_EQ("3.4", "", u3.getPath());
 
 		vmime::utility::url u4("", "");
 
 		VASSERT_EQ("4.1", true, parseHelper(u4, "proto://host/path?p1=%3D&%3D=v2"));
-		VASSERT_EQ("4.2", "=", u4.getParams().getProperty <vmime::string>("p1"));
-		VASSERT_EQ("4.3", "v2", u4.getParams().getProperty <vmime::string>("="));
+		VASSERT_EQ("4.2", "=", u4.getParams()["p1"]);
+		VASSERT_EQ("4.3", "v2", u4.getParams()["="]);
 		VASSERT_EQ("4.4", "/path", u4.getPath());
 	}
 
@@ -211,14 +211,17 @@ VMIME_TEST_SUITE_BEGIN(urlTest)
 		VASSERT_EQ("2", "proto://host", static_cast <vmime::string>(u2));
 
 		vmime::utility::url u3("proto", "host");
-		u3.getParams().setProperty("p1", "v1");
+		u3.getParams()["p1"] = "v1";
 		VASSERT_EQ("3.1", "proto://host/?p1=v1",
 			static_cast <vmime::string>(u3));
-		u3.getParams().setProperty("p2", "v2");
+		u3.getParams()["p2"] = "v2";
 		VASSERT_EQ("3.2", "proto://host/?p1=v1&p2=v2",
 			static_cast <vmime::string>(u3));
-		u3.getParams().setProperty("&", "=");
-		VASSERT_EQ("3.3", "proto://host/?p1=v1&p2=v2&%26=%3D",
+
+		// Test special characters
+		u3.getParams().clear();
+		u3.getParams()["&"] = "=";
+		VASSERT_EQ("3.3", "proto://host/?%26=%3D",
 			static_cast <vmime::string>(u3));
 	}
 
diff --git a/vmime/utility/url.hpp b/vmime/utility/url.hpp
index 825d2a32..84aba618 100644
--- a/vmime/utility/url.hpp
+++ b/vmime/utility/url.hpp
@@ -162,13 +162,13 @@ public:
 	  *
 	  * @return parameters
 	  */
-	const propertySet& getParams() const;
+	const std::map <string, string>& getParams() const;
 
 	/** Return the parameters of the URL.
 	  *
 	  * @return parameters
 	  */
-	propertySet& getParams();
+	std::map <string, string>& getParams();
 
 	/** Build a string URL from this object.
 	  */
@@ -196,7 +196,7 @@ private:
 
 	string m_path;
 
-	propertySet m_params;
+	std::map <string, string> m_params;
 };