diff --git a/include/libtorrent/escape_string.hpp b/include/libtorrent/escape_string.hpp
index 841f9c7ce..4745560eb 100755
--- a/include/libtorrent/escape_string.hpp
+++ b/include/libtorrent/escape_string.hpp
@@ -34,6 +34,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #define TORRENT_ESCAPE_STRING_HPP_INCLUDED
 
 #include <string>
+#include <boost/optional.hpp>
 #include "libtorrent/config.hpp"
 
 namespace libtorrent
@@ -43,10 +44,12 @@ namespace libtorrent
 	std::string TORRENT_EXPORT escape_path(const char* str, int len);
 
 	// encodes a string using the base64 scheme
-	TORRENT_EXPORT std::string base64encode(const std::string& s);
+	TORRENT_EXPORT std::string base64encode(std::string const& s);
 	// encodes a string using the base32 scheme
-	TORRENT_EXPORT std::string base32encode(const std::string& s);
+	TORRENT_EXPORT std::string base32encode(std::string const& s);
 
+	TORRENT_EXPORT boost::optional<std::string> url_has_argument(
+		std::string const& url, std::string argument);
 }
 
 #endif // TORRENT_ESCAPE_STRING_HPP_INCLUDED
diff --git a/src/escape_string.cpp b/src/escape_string.cpp
index 6a6658715..7477a81d5 100755
--- a/src/escape_string.cpp
+++ b/src/escape_string.cpp
@@ -38,7 +38,8 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <iomanip>
 #include <cctype>
 #include <algorithm>
-#include <iostream>
+
+#include <boost/optional.hpp>
 
 #include "libtorrent/assert.hpp"
 
@@ -85,7 +86,6 @@ namespace libtorrent
 		return ret;
 	}
 
-
 	std::string escape_string(const char* str, int len)
 	{
 		TORRENT_ASSERT(str != 0);
@@ -220,7 +220,6 @@ namespace libtorrent
 		unsigned char inbuf[5];
 		unsigned char outbuf[8];
 	
-		std::cerr << "base32(" << s << ") = ";
 		std::string ret;
 		for (std::string::const_iterator i = s.begin(); i != s.end();)
 		{
@@ -261,8 +260,29 @@ namespace libtorrent
 				ret += '=';
 			}
 		}
-		std::cerr << ret << std::endl;
 		return ret;
 	}
+
+	boost::optional<std::string> url_has_argument(
+		std::string const& url, std::string argument)
+	{
+		size_t i = url.find('?');
+		if (i == std::string::npos) return boost::optional<std::string>();
+		++i;
+
+		argument += '=';
+
+		if (url.compare(i, argument.size(), argument) == 0)
+		{
+			size_t pos = i + argument.size();
+			return url.substr(pos, url.find('&', pos) - pos);
+		}
+		argument.insert(0, "&");
+		i = url.find(argument, i);
+		if (i == std::string::npos) return boost::optional<std::string>();
+		size_t pos = i + argument.size();
+		return url.substr(pos, url.find('&', pos) - pos);
+	}
+
 }
 
diff --git a/src/http_tracker_connection.cpp b/src/http_tracker_connection.cpp
index 86d21e494..91c305d17 100755
--- a/src/http_tracker_connection.cpp
+++ b/src/http_tracker_connection.cpp
@@ -89,19 +89,6 @@ namespace
 
 namespace
 {
-	bool url_has_argument(std::string const& url, std::string argument)
-	{
-		size_t i = url.find('?');
-		if (i == std::string::npos) return false;
-
-		argument += '=';
-
-		if (url.compare(i + 1, argument.size(), argument) == 0) return true;
-		argument.insert(0, "&");
-		return url.find(argument, i)
-			!= std::string::npos;
-	}
-
 	char to_lower(char c) { return std::tolower(c); }
 }
 
diff --git a/test/test_primitives.cpp b/test/test_primitives.cpp
index 73462aaed..761998e71 100644
--- a/test/test_primitives.cpp
+++ b/test/test_primitives.cpp
@@ -91,6 +91,8 @@ int test_main()
 	TEST_CHECK(base64encode("fooba") == "Zm9vYmE=");
 	TEST_CHECK(base64encode("foobar") == "Zm9vYmFy");
 
+	// base32 test vectors from http://www.faqs.org/rfcs/rfc4648.html
+
    TEST_CHECK(base32encode("") == "");
    TEST_CHECK(base32encode("f") == "MY======");
    TEST_CHECK(base32encode("fo") == "MZXQ====");
@@ -99,6 +101,17 @@ int test_main()
    TEST_CHECK(base32encode("fooba") == "MZXW6YTB");
    TEST_CHECK(base32encode("foobar") == "MZXW6YTBOI======");
 
+	// url_has_argument
+
+	TEST_CHECK(!url_has_argument("http://127.0.0.1/test", "test"));
+	TEST_CHECK(!url_has_argument("http://127.0.0.1/test?foo=24", "bar"));
+	TEST_CHECK(*url_has_argument("http://127.0.0.1/test?foo=24", "foo") == "24");
+	TEST_CHECK(*url_has_argument("http://127.0.0.1/test?foo=24&bar=23", "foo") == "24");
+	TEST_CHECK(*url_has_argument("http://127.0.0.1/test?foo=24&bar=23", "bar") == "23");
+	TEST_CHECK(*url_has_argument("http://127.0.0.1/test?foo=24&bar=23&a=e", "bar") == "23");
+	TEST_CHECK(*url_has_argument("http://127.0.0.1/test?foo=24&bar=23&a=e", "a") == "e");
+	TEST_CHECK(!url_has_argument("http://127.0.0.1/test?foo=24&bar=23&a=e", "b"));
+
 	// HTTP request parser
 
 	http_parser parser;