diff --git a/bleach/__init__.py b/bleach/__init__.py
index 09f322fa..e80e8d53 100644
--- a/bleach/__init__.py
+++ b/bleach/__init__.py
@@ -59,7 +59,7 @@
 url_re = re.compile(
     r"""\(*  # Match any opening parentheses.
     \b(?<![@.])(?:\w[\w-]*:/{0,3}(?:(?:\w+:)?\w+@)?)?  # http://
-    ([\w-]+\.)+(?:%s)(?!\.\w)\b   # xx.yy.tld
+    ([\w-]+\.)+(?:%s)(?:\:\d+)?(?!\.\w)\b   # xx.yy.tld(:##)?
     (?:[/?][^\s\{\}\|\\\^\[\]`<>"]*)?
         # /path/zz (excluding "unsafe" chars from RFC 1738,
         # except for # and ~, which happen in practice)
diff --git a/bleach/tests/test_links.py b/bleach/tests/test_links.py
index bcc652ec..948d9997 100644
--- a/bleach/tests/test_links.py
+++ b/bleach/tests/test_links.py
@@ -242,8 +242,7 @@ def test_sarcasm():
 
 
 def test_wrapping_parentheses():
-    """urls wrapped in balanced paranthesis shall not include them in the href
-    """
+    """URLs wrapped in parantheses should not include them."""
     out = u'%s<a href="http://%s" rel="nofollow">%s</a>%s'
 
     tests = (
@@ -277,3 +276,21 @@ def check(test, expected_output):
 
     for test, expected_output in tests:
         yield check, test, expected_output
+
+
+def test_ports():
+    """URLs can contain port numbers."""
+    tests = (
+        ('http://foo.com:8000', ('http://foo.com:8000', '')),
+        ('http://foo.com:8000/', ('http://foo.com:8000/', '')),
+        ('http://bar.com:xkcd', ('http://bar.com', ':xkcd')),
+        ('http://foo.com:81/bar', ('http://foo.com:81/bar', '')),
+        ('http://foo.com:', ('http://foo.com', ':')),
+    )
+
+    def check(test, output):
+        eq_(u'<a href="{0}" rel="nofollow">{0}</a>{1}'.format(*output),
+            linkify(test))
+
+    for test, output in tests:
+        yield check, test, output