diff --git a/validate.py b/validate.py
index e5375f2..6c94f8e 100644
--- a/validate.py
+++ b/validate.py
@@ -2,6 +2,7 @@ import json
 from StringIO import StringIO
 
 import validator.main
+import validator.constants
 import validator.testcases.targetapplication
 from validator.errorbundler import ErrorBundle
 from validator.constants import PACKAGE_ANY
@@ -9,7 +10,8 @@ from validator.constants import PACKAGE_ANY
 
 def validate(path, format="json",
              approved_applications="validator/app_versions.json",
-             determined=True):
+             determined=True,
+             spidermonkey=None):
     "Perform validation in one easy step!"
 
     output = StringIO()
@@ -20,6 +22,9 @@ def validate(path, format="json",
 
     bundle = ErrorBundle(pipe=output, no_color=True, listed=True,
                          determined=determined)
+    if spidermonkey is not None:
+        bundle.save_resource("SPIDERMONKEY", spidermonkey)
+
     validator.main.prepare_package(bundle, path, PACKAGE_ANY)
 
     # Write the results to the pipe
diff --git a/validator/constants.py b/validator/constants.py
index 8a37c3d..a529d55 100644
--- a/validator/constants.py
+++ b/validator/constants.py
@@ -30,3 +30,8 @@ if not os.path.exists(SPIDERMONKEY_INSTALLATION):
         # The fallback is simply to disable JS tests.
         SPIDERMONKEY_INSTALLATION = None
 
+try:
+    from validator.constants_local import *
+except ImportError:
+    pass
+
diff --git a/validator/submain.py b/validator/submain.py
index 4af7774..04cb3fb 100644
--- a/validator/submain.py
+++ b/validator/submain.py
@@ -9,13 +9,6 @@ from validator.xpi import XPIManager
 from validator.rdf import RDFParser
 from validator import decorator
 
-# This is modeled after Zamboni's settings_local.py implementation, but
-# it is only designed to allow the constants to be overridden.
-try:
-    import validator.constants_local as constants
-except ImportError:
-    import validator.constants as constants
-
 from constants import *
 
 types = {0: "Unknown",
diff --git a/validator/testcases/javascript/traverser.py b/validator/testcases/javascript/traverser.py
index 35d66c4..07e28ba 100644
--- a/validator/testcases/javascript/traverser.py
+++ b/validator/testcases/javascript/traverser.py
@@ -12,6 +12,11 @@ class MockBundler:
         self.final_context = None
         self.tier = 4
 
+    def get_resource(self, name):
+        "Represents a resource store"
+
+        return False
+
     def error(self, id, title, description, file="",
               line=1, column=0, context=None):
         "Represents a mock error"
diff --git a/validator/testcases/scripting.py b/validator/testcases/scripting.py
index 7a5a543..9429d21 100644
--- a/validator/testcases/scripting.py
+++ b/validator/testcases/scripting.py
@@ -6,14 +6,14 @@ import subprocess
 import tempfile
 
 import validator.testcases.javascript.traverser as traverser
+from validator.constants import SPIDERMONKEY_INSTALLATION
 from validator.contextgenerator import ContextGenerator
-import validator.submain as submain
-SPIDERMONKEY = submain.constants.SPIDERMONKEY_INSTALLATION
 
 def test_js_file(err, name, data, filename=None, line=0):
     "Tests a JS file by parsing and analyzing its tokens"
     
-    if SPIDERMONKEY is None:
+    if SPIDERMONKEY_INSTALLATION is None and \
+           not err.get_resource("SPIDERMONKEY"):
         return
 
     # The filename is 
@@ -21,7 +21,8 @@ def test_js_file(err, name, data, filename=None, line=0):
         filename = name
     
     # Get the AST tree for the JS code
-    tree = _get_tree(name, data)
+    tree = _get_tree(name, data, err.get_resource("SPIDERMONKEY") or
+                         SPIDERMONKEY_INSTALLATION)
     if tree is None:
         return None
     
@@ -48,9 +49,6 @@ def test_js_file(err, name, data, filename=None, line=0):
 def test_js_snippet(err, data, filename=None, line=0):
     "Process a JS snippet by passing it through to the file tester."
     
-    if SPIDERMONKEY is None:
-        return
-    
     if filename is not None:
         name = "%s:%d" % (filename, line)
     else:
@@ -96,7 +94,7 @@ def _regex_tests(err, data, filename):
                       context=c)
 
 
-def _get_tree(name, code):
+def _get_tree(name, code, shell=SPIDERMONKEY_INSTALLATION):
    
     # TODO : It seems appropriate to cut the `name` parameter out if the
     # parser is going to be installed locally.
@@ -120,7 +118,7 @@ def _get_tree(name, code):
     temp.write(data)
     temp.flush() # This is very important
 
-    cmd = [SPIDERMONKEY, "-f", temp.name]
+    cmd = [shell, "-f", temp.name]
     shell = subprocess.Popen(cmd,
 	                     shell=False,
 			     stderr=subprocess.PIPE,
diff --git a/validator/testcases/targetapplication.py b/validator/testcases/targetapplication.py
index 484c325..f122ae8 100644
--- a/validator/testcases/targetapplication.py
+++ b/validator/testcases/targetapplication.py
@@ -1,7 +1,5 @@
 from validator import decorator
-import validator.submain as submain
-PACKAGE_DICTIONARY = submain.constants.PACKAGE_DICTIONARY
-FF4_MIN = submain.constants.FF4_MIN
+from validator.constants import PACKAGE_DICTIONARY, FF4_MIN
 
 APPLICATIONS = {
     "{ec8030f7-c20a-464f-9b0e-13a3a9e97384}": "firefox",