diff --git a/PHPCI/Model/Build/MercurialBuild.php b/PHPCI/Model/Build/MercurialBuild.php
index 0f38940b..8e59ea95 100644
--- a/PHPCI/Model/Build/MercurialBuild.php
+++ b/PHPCI/Model/Build/MercurialBuild.php
@@ -42,7 +42,7 @@ class MercurialBuild extends Build
         }
 
         if (!$success) {
-            $builder->logFailure('Failed to clone remote git repository.');
+            $builder->logFailure('Failed to clone remote hg repository.');
             return false;
         }
 
@@ -57,16 +57,34 @@ class MercurialBuild extends Build
         return $builder->executeCommand('hg clone %s "%s" -r %s', $this->getCloneUrl(), $cloneTo, $this->getBranch());
     }
 
+    /**
+     * Create an SSH key file on disk for this build.
+     * @param $cloneTo
+     * @return string
+     */
+    protected function writeSshKey($cloneTo)
+    {
+        $keyPath = dirname($cloneTo . '/temp');
+        $keyFile = $keyPath . '.key';
+
+        // Write the contents of this project's hg key to the file:
+        file_put_contents($keyFile, $this->getProject()->getSshPrivateKey());
+        chmod($keyFile, 0600);
+
+        // Return the filename:
+        return $keyFile;
+    }
+
     /**
      * Use an SSH-based Mercurial clone.
      */
     protected function cloneBySsh(Builder $builder, $cloneTo)
     {
-        $keyFile = $this->writeSshKey();
+        $keyFile = $this->writeSshKey($cloneTo);
 
-        // Do the git clone:
-        $cmd = 'hg clone --ssh "ssh -i '.$keyFile.'" %s "%s"';
-        $success = $builder->executeCommand($cmd, $this->getCloneUrl(), $cloneTo);
+        // Do the hg clone:
+        $cmd = 'hg clone --ssh "ssh -i '.$keyFile.'" %s "%s" -r %s';
+        $success = $builder->executeCommand($cmd, $this->getCloneUrl(), $cloneTo, $this->getBranch());
 
         if ($success) {
             $success = $this->postCloneSetup($builder, $cloneTo);