--- a/client.py
+++ b/client.py
@@ -64,20 +64,26 @@ def do_hg_pull(dir, repository, hg):
 
 def do_cvs_checkout(modules, tag, cvsroot, cvs, checkoutdir):
     """Check out a CVS directory into the mozilla/ subdirectory.
     modules is a list of directories to check out, e.g. ['extensions/irc']
     """
     for module in modules:
         (parent, leaf) = os.path.split(module)
         print "CVS checkout begin: " + datetime.datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S UTC")
-        check_call_noisy([cvs, '-d', cvsroot, '-q',
-                          'checkout', '-P', '-r', tag, '-d', leaf,
-                          'mozilla/%s' % module],
-                         cwd=os.path.join(topsrcdir, checkoutdir, parent))
+        if tag == 'HEAD':
+            check_call_noisy([cvs, '-d', cvsroot, '-q',
+                              'checkout', '-P', '-A', '-d', leaf,
+                              'mozilla/%s' % module],
+                             cwd=os.path.join(topsrcdir, checkoutdir, parent))
+        else:
+            check_call_noisy([cvs, '-d', cvsroot, '-q',
+                              'checkout', '-P', '-r', tag, '-d', leaf,
+                              'mozilla/%s' % module],
+                             cwd=os.path.join(topsrcdir, checkoutdir, parent))
         print "CVS checkout end: " + datetime.datetime.utcnow().strftime("%Y-%m-%d %H:%M:%S UTC")
 
 o = OptionParser(usage="client.py [options] checkout")
 o.add_option("-m", "--comm-repo", dest="comm_repo",
              default=None,
              help="URL of comm (Calendar/Mail/Suite) repository to pull from (default: use hg default in .hg/hgrc)")
 o.add_option("--skip-comm", dest="skip_comm",
              action="store_true", default=False,