diff --git a/tests/test_udp_src.py b/tests/test_udp_src.py
new file mode 100644
index 0000000..e8fa505
--- /dev/null
+++ b/tests/test_udp_src.py
@@ -0,0 +1,83 @@
+#!/usr/bin/python
+
+import socket
+import socks
+
+
+SERVER_IP = '127.0.0.1'
+SERVER_PORT = 1081
+
+
+if __name__ == '__main__':
+    # Test 1: same source port IPv4
+    sock_out = socks.socksocket(socket.AF_INET, socket.SOCK_DGRAM,
+                                socket.SOL_UDP)
+    sock_out.set_proxy(socks.SOCKS5, SERVER_IP, SERVER_PORT)
+    sock_out.bind(('127.0.0.1', 9000))
+
+    sock_in1 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM,
+                             socket.SOL_UDP)
+    sock_in2 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM,
+                             socket.SOL_UDP)
+
+    sock_in1.bind(('127.0.0.1', 9001))
+    sock_in2.bind(('127.0.0.1', 9002))
+
+    sock_out.sendto(b'data', ('127.0.0.1', 9001))
+    result1 = sock_in1.recvfrom(8)
+
+    sock_out.sendto(b'data', ('127.0.0.1', 9002))
+    result2 = sock_in2.recvfrom(8)
+
+    sock_out.close()
+    sock_in1.close()
+    sock_in2.close()
+
+    # make sure they're from the same source port
+    assert result1 == result2
+
+    # Test 2: same source port IPv6
+    # try again from the same port but IPv6
+    sock_out = socks.socksocket(socket.AF_INET, socket.SOCK_DGRAM,
+                                socket.SOL_UDP)
+    sock_out.set_proxy(socks.SOCKS5, SERVER_IP, SERVER_PORT)
+    sock_out.bind(('127.0.0.1', 9000))
+
+    sock_in1 = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM,
+                             socket.SOL_UDP)
+    sock_in2 = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM,
+                             socket.SOL_UDP)
+
+    sock_in1.bind(('::1', 9001))
+    sock_in2.bind(('::1', 9002))
+
+    sock_out.sendto(b'data', ('::1', 9001))
+    result1 = sock_in1.recvfrom(8)
+
+    sock_out.sendto(b'data', ('::1', 9002))
+    result2 = sock_in2.recvfrom(8)
+
+    sock_out.close()
+    sock_in1.close()
+    sock_in2.close()
+
+    # make sure they're from the same source port
+    assert result1 == result2
+
+    # Test 3: different source ports IPv6
+    sock_out = socks.socksocket(socket.AF_INET, socket.SOCK_DGRAM,
+                                socket.SOL_UDP)
+    sock_out.set_proxy(socks.SOCKS5, SERVER_IP, SERVER_PORT)
+    sock_out.bind(('127.0.0.1', 9003))
+
+    sock_in1 = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM,
+                             socket.SOL_UDP)
+    sock_in1.bind(('::1', 9001))
+    sock_out.sendto(b'data', ('::1', 9001))
+    result3 = sock_in1.recvfrom(8)
+
+    # make sure they're from different source ports
+    assert result1 != result3
+
+    sock_out.close()
+    sock_in1.close()