diff --git a/manifest_xml.py b/manifest_xml.py
index 890c954..8b57bf5 100644
--- a/manifest_xml.py
+++ b/manifest_xml.py
@@ -38,8 +38,9 @@
 LOCAL_MANIFEST_NAME = 'local_manifest.xml'
 LOCAL_MANIFESTS_DIR_NAME = 'local_manifests'
 
-urllib.parse.uses_relative.extend(['ssh', 'git'])
-urllib.parse.uses_netloc.extend(['ssh', 'git'])
+# urljoin gets confused if the scheme is not known.
+urllib.parse.uses_relative.extend(['ssh', 'git', 'persistent-https', 'rpc'])
+urllib.parse.uses_netloc.extend(['ssh', 'git', 'persistent-https', 'rpc'])
 
 class _Default(object):
   """Project defaults within the manifest."""
@@ -85,21 +86,13 @@
     # urljoin will gets confused over quite a few things.  The ones we care
     # about here are:
     # * no scheme in the base url, like <hostname:port>
-    # * persistent-https://
-    # * rpc://
-    # We handle this by replacing these with obscure protocols
-    # and then replacing them with the original when we are done.
-    # gopher -> <none>
-    # wais -> persistent-https
-    # nntp -> rpc
+    # We handle no scheme by replacing it with an obscure protocol, gopher
+    # and then replacing it with the original when we are done.
+
     if manifestUrl.find(':') != manifestUrl.find('/') - 1:
-      manifestUrl = 'gopher://' + manifestUrl
-    manifestUrl = re.sub(r'^persistent-https://', 'wais://', manifestUrl)
-    manifestUrl = re.sub(r'^rpc://', 'nntp://', manifestUrl)
-    url = urllib.parse.urljoin(manifestUrl, url)
-    url = re.sub(r'^gopher://', '', url)
-    url = re.sub(r'^wais://', 'persistent-https://', url)
-    url = re.sub(r'^nntp://', 'rpc://', url)
+      url = urllib.parse.urljoin('gopher://' + manifestUrl, url)[9:]
+    else:
+      url = urllib.parse.urljoin(manifestUrl, url)
     return url
 
   def ToRemoteSpec(self, projectName):
diff --git a/project.py b/project.py
index 1245fa2..e76d639 100644
--- a/project.py
+++ b/project.py
@@ -1326,6 +1326,8 @@
     if not ID_RE.match(self.revisionExpr):
       # in case of manifest sync the revisionExpr might be a SHA1
       branch.merge = self.revisionExpr
+      if not branch.merge.startswith('refs/'):
+        branch.merge = R_HEADS + branch.merge
     branch.Save()
 
     if cnt_mine > 0 and self.rebase:
@@ -1394,6 +1396,8 @@
     branch = self.GetBranch(name)
     branch.remote = self.GetRemote(self.remote.name)
     branch.merge = self.revisionExpr
+    if not branch.merge.startswith('refs/'):
+      branch.merge = R_HEADS + self.revisionExpr
     revid = self.GetRevisionId(all_refs)
 
     if head.startswith(R_HEADS):
@@ -1865,7 +1869,8 @@
 
     shallowfetch = self.config.GetString('repo.shallowfetch')
     if shallowfetch and shallowfetch != ' '.join(spec):
-      GitCommand(self, ['fetch', '--unshallow', name] + shallowfetch.split(),
+      GitCommand(self, ['fetch', '--depth=2147483647', name]
+                 + shallowfetch.split(),
                  bare=True, ssh_proxy=ssh_proxy).Wait()
     if depth:
       self.config.SetString('repo.shallowfetch', ' '.join(spec))
diff --git a/repo b/repo
index 960e76f..f12354a 100755
--- a/repo
+++ b/repo
@@ -20,7 +20,7 @@
 # limitations under the License.
 
 # increment this whenever we make important changes to this script
-VERSION = (1, 22)
+VERSION = (1, 21)
 
 # increment this if the MAINTAINER_KEYS block is modified
 KEYRING_VERSION = (1, 2)
@@ -102,7 +102,7 @@
 """
 
 GIT = 'git'                     # our git command
-MIN_GIT_VERSION = (1, 8, 2)     # minimum supported git version
+MIN_GIT_VERSION = (1, 7, 2)     # minimum supported git version
 repodir = '.repo'               # name of repo's private directory
 S_repo = 'repo'                 # special repo repository
 S_manifests = 'manifests'       # special manifest repository