import socket
import threading
import ftplib
import time

from unittest import TestCase
from test import test_support

def server(evt):
    serv = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    serv.settimeout(3)
    serv.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    serv.bind(("", 9091))
    serv.listen(5)
    try:
        conn, addr = serv.accept()
    except socket.timeout:
        pass
    else:
        conn.send("1 Hola mundo\n")
        conn.close()
    finally:
        serv.close()
        evt.set()

class GeneralTests(TestCase):

    def setUp(self):
        ftplib.FTP.port = 9091
        self.evt = threading.Event()
        threading.Thread(target=server, args=(self.evt,)).start()
        time.sleep(.1)

    def tearDown(self):
        self.evt.wait()

    def testBasic(self):
        # do nothing
        ftplib.FTP()

        # connects
        ftp = ftplib.FTP("localhost")
        ftp.sock.close()

    def testTimeoutDefault(self):
        # default
        ftp = ftplib.FTP("localhost")
        self.assertTrue(ftp.sock.gettimeout() is None)
        ftp.sock.close()

    def testTimeoutValue(self):
        # a value
        ftp = ftplib.FTP("localhost", timeout=30)
        self.assertEqual(ftp.sock.gettimeout(), 30)
        ftp.sock.close()

    def testTimeoutConnect(self):
        ftp = ftplib.FTP()
        ftp.connect("localhost", timeout=30)
        self.assertEqual(ftp.sock.gettimeout(), 30)
        ftp.sock.close()

    def testTimeoutDifferentOrder(self):
        ftp = ftplib.FTP(timeout=30)
        ftp.connect("localhost")
        self.assertEqual(ftp.sock.gettimeout(), 30)
        ftp.sock.close()

    def testTimeoutDirectAccess(self):
        ftp = ftplib.FTP()
        ftp.timeout = 30
        ftp.connect("localhost")
        self.assertEqual(ftp.sock.gettimeout(), 30)
        ftp.sock.close()

    def testTimeoutNone(self):
        # None, having other default
        previous = socket.getdefaulttimeout()
        socket.setdefaulttimeout(30)
        try:
            ftp = ftplib.FTP("localhost", timeout=None)
        finally:
            socket.setdefaulttimeout(previous)
        self.assertEqual(ftp.sock.gettimeout(), 30)
        ftp.close()



def test_main(verbose=None):
    test_support.run_unittest(GeneralTests)

if __name__ == '__main__':
    test_main()

@@ -126,16 +126,23 @@
 rver(evt
+, ready
 ):%0A    s
@@ -328,16 +328,32 @@
 sten(5)%0A
+    ready.set()%0A
     try:
@@ -664,24 +664,58 @@
 ing.Event()%0A
+        ready = threading.Event()%0A
         thre
@@ -757,16 +757,22 @@
 elf.evt,
+ ready
 )).start
@@ -786,21 +786,19 @@
     
-time.sleep(.1
+ready.wait(
 )%0A%0A 

Use an event variable to wait for the server to be ready, not time.sleep().