diff --git a/src/IDF/Scm/Monotone.php b/src/IDF/Scm/Monotone.php
index f5944d6..ecec8c7 100644
--- a/src/IDF/Scm/Monotone.php
+++ b/src/IDF/Scm/Monotone.php
@@ -135,13 +135,13 @@ class IDF_Scm_Monotone extends IDF_Scm
     /**
      * @see IDF_Scm::getArchiveStream
      */
-    public function getArchiveStream($commit, $prefix='repository/')
+    public function getArchiveStream($commit, $prefix = null)
     {
         $revs = $this->_resolveSelector($commit);
         // sanity: this should actually not happen, because the
         // revision is validated before already
         if (count($revs) == 0) {
-            return new Pluf_HTTP_Response_NotFound();
+            throw new IDF_Scm_Exception("$commit is not a valid revision");
         }
         return new IDF_Scm_Monotone_ZipRender($this->stdio, $revs[0]);
     }
diff --git a/test/IDF/Scm/MonotoneTest.php b/test/IDF/Scm/MonotoneTest.php
new file mode 100644
index 0000000..a54502d
--- /dev/null
+++ b/test/IDF/Scm/MonotoneTest.php
@@ -0,0 +1,249 @@
+<?php
+/* -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+# ***** BEGIN LICENSE BLOCK *****
+# This file is part of InDefero, an open source project management application.
+# Copyright (C) 2011 Céondo Ltd and contributors.
+#
+# InDefero is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# InDefero is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#
+# ***** END LICENSE BLOCK ***** */
+
+class MonotoneStdioMock implements IDF_Scm_Monotone_IStdio
+{
+    // unused
+    public function __construct(IDF_Project $project) {}
+
+    // unused
+    public function start() {}
+
+    // unused
+    public function stop() {}
+
+    private $outputMap = array();
+
+    public function setExpectedOutput(array $args, array $options, $output)
+    {
+        @$this->outputMap[serialize($args)][serialize($options)] = $output;
+    }
+
+    public function exec(array $args, array $options = array())
+    {
+        $optoutputs = @$this->outputMap[serialize($args)];
+        if ($optoutputs === null) {
+            return false;
+        }
+
+        return @$optoutputs[serialize($options)];
+    }
+
+    // unused
+    public function getLastOutOfBandOutput() {}
+}
+
+class IDF_Scm_Monotone_Test extends PHPUnit_Framework_TestCase
+{
+    private $proj = null;
+
+    public function setUp()
+    {
+        $this->proj = new IDF_Project();
+        $this->proj->id = 1;
+        $this->proj->name = $this->proj->shortname = 'Test';
+        $this->proj->create();
+
+        $this->proj->getConf()->setVal('mtn_master_branch', 'master.branch');
+    }
+
+    public function tearDown()
+    {
+        $this->proj->delete();
+    }
+
+    public function createMock(array $args = array(), array $options = array(), $output = null)
+    {
+        $instance = new IDF_Scm_Monotone($this->proj, new MonotoneStdioMock($this->proj));
+        if (count($args) > 0) {
+            $instance->getStdio()->setExpectedOutput($args, $options, $output);
+        }
+        return $instance;
+    }
+
+    public function testGetStdio()
+    {
+        $instance = $this->createMock();
+        $this->assertNotNull($instance->getStdio());
+    }
+
+    public function testGetRepositorySize()
+    {
+        $this->markTestSkipped('Cannot mock real repository file');
+    }
+
+    public function testIsAvailable()
+    {
+        $instance = $this->createMock(array('interface_version'), array(), '13.0');
+        $this->assertTrue($instance->isAvailable());
+
+        $instance->getStdio()->setExpectedOutput(array('interface_version'), array(), '12.7');
+        $this->assertFalse($instance->isAvailable());
+
+        $instance->getStdio()->setExpectedOutput(array('interface_version'), array(), 'foo');
+        $this->assertFalse($instance->isAvailable());
+    }
+
+    public function testGetBranches()
+    {
+        $instance = $this->createMock(array('branches'), array(), "foo\nbar.baz");
+        $this->assertEquals(array(
+              'h:foo' => 'foo',
+              'h:bar.baz' => 'bar.baz',
+        ), $instance->getBranches());
+    }
+
+    public function testGetMainBranch()
+    {
+        $instance = $this->createMock();
+        $this->assertEquals('master.branch', $instance->getMainBranch());
+        $instance->project->getConf()->setVal('mtn_master_branch', '');
+        $this->assertEquals('*', $instance->getMainBranch());
+    }
+
+    public function testGetArchiveStream()
+    {
+        $instance = $this->createMock(array('select', 'abc123'), array(), "1234567890123456789012345678901234567890\n");
+        $ziprender = $instance->getArchiveStream('abc123');
+        $this->assertTrue($ziprender instanceof IDF_Scm_Monotone_ZipRender);
+
+        $thrown = false;
+        try {
+            $ziprender = $instance->getArchiveStream('foo');
+        }
+        catch (IDF_Scm_Exception $e) {
+            $thrown = true;
+        }
+        $this->assertTrue($thrown);
+    }
+
+    public function testInBranches()
+    {
+        // returns the branches the given commit is in
+    }
+
+    public function testGetTags()
+    {
+        $stdio =<<<END
+     tag "foo-1.0"
+revision [5db0a3dfb923d050d096c7c63ab23592c7ebc4c3]
+  signer [de84b575d5e47254393eba49dce9dc4db98ed42d]
+branches "org.company.foo"
+
+     tag "foo-1.1"
+revision [a4a773ecc74c1b80a03c60f57c6cc7bec85fb2cf]
+  signer [7fe029d85af4de40700778b9784ef488fac2c79c]
+branches "org.company.foo"
+
+     tag "bar-1.0"
+revision [09a00eb14482dde8876436351c6c4392b1e7f0b1]
+  signer [7fe029d85af4de40700778b9784ef488fac2c79c]
+branches "org.company.bar" "org.company.bar.release-1.0"
+END;
+        $instance = $this->createMock(array('tags'), array(), $stdio);
+        $this->assertEquals(array(
+            't:foo-1.0' => 'foo-1.0',
+            't:foo-1.1' => 'foo-1.1',
+            't:bar-1.0' => 'bar-1.0',
+        ), $instance->getTags());
+    }
+
+    public function testInTags()
+    {
+        // returns the tags that are attached to the given commit
+    }
+
+    public function testGetTree()
+    {
+        // test root and sub tree fetching
+    }
+
+    public function testFindAuthor()
+    {
+        $this->markTestSkipped('This functionality here should reside in IDF_Scm');
+    }
+
+    public function testGetAnonymousAccessUrl()
+    {
+        // test the generation of the anonymous remote URL
+    }
+
+    public function testGetAuthAccessUrl()
+    {
+        // test the generation of the authenticated remote URL (only really visible for SSH)
+    }
+
+    public function testFactory()
+    {
+        $this->markTestSkipped('Cannot mock real repository');
+    }
+
+    public function testValidateRevision()
+    {
+        // test valid, invalid and ambigious
+    }
+
+    public function testDisambiguateRevision()
+    {
+        // test for array of commit objects
+    }
+
+    public function testGetPathInfo()
+    {
+        // return the info (creation date, last commit, et cetera) for a single file and commit
+    }
+
+    public function testGetFile()
+    {
+        // test cmd_only and full file fetching
+    }
+
+    public function testGetChanges()
+    {
+        // test retrieving the changes of a specific revision
+    }
+
+    public function testGetCommit()
+    {
+        // test get commit information with and without a diff text
+        // test multiple branches, dates, authors, aso
+    }
+
+    public function testGetExtraProperties()
+    {
+        // test array('parents' => array(rev1, rev2, ...)) or array() if root revision
+    }
+
+    public function testIsCommitLarge()
+    {
+        // test for true / false with commits with more than 100 changes
+    }
+
+    public function testGetChangeLog()
+    {
+        // test with no commit, empty $n
+        // test logging stops at unknown branches
+        // test logging stops at $n
+    }
+}
+