diff --git a/Lib/httplib.py b/Lib/httplib.py
index 526509c..e1ace4d 100644
--- a/Lib/httplib.py
+++ b/Lib/httplib.py
@@ -879,6 +879,9 @@
                         host_enc = self.host.encode("ascii")
                     except UnicodeEncodeError:
                         host_enc = self.host.encode("idna")
+                    # Wrap the IPv6 Host Header with [] (RFC 2732)
+                    if host_enc.find(':') >= 0:
+                        host_enc = "[" + host_enc + "]"
                     if self.port == self.default_port:
                         self.putheader('Host', host_enc)
                     else: