diff --git a/rply/lexergenerator.py b/rply/lexergenerator.py
index 62d0bb9..d806a37 100644
--- a/rply/lexergenerator.py
+++ b/rply/lexergenerator.py
@@ -1,7 +1,17 @@
 import re
 
+from rply.lexer import Lexer
+
 try:
     import rpython
+    from rpython.rlib.objectmodel import we_are_translated
+except ImportError:
+    rpython = None
+
+    def we_are_translated():
+        return False
+
+if we_are_translated():
     from rpython.annotator import model
     from rpython.annotator.bookkeeper import getbookkeeper
     from rpython.rlib.objectmodel import instantiate, hlinvoke
@@ -14,10 +24,6 @@
     from rpython.rtyper.lltypesystem.rstr import STR, string_repr
     from rpython.rtyper.rmodel import Repr
     from rpython.tool.pairtype import pairtype
-except ImportError:
-    rpython = None
-
-from rply.lexer import Lexer
 
 
 class Rule(object):
@@ -104,7 +110,8 @@ def build(self):
         """
         return Lexer(self.rules, self.ignore_rules)
 
-if rpython:
+
+if we_are_translated():
     class RuleEntry(ExtRegistryEntry):
         _type_ = Rule
 
diff --git a/tests/test_ztranslation.py b/tests/test_ztranslation.py
index d51452c..a1b90a4 100644
--- a/tests/test_ztranslation.py
+++ b/tests/test_ztranslation.py
@@ -2,8 +2,14 @@
 
 try:
     from rpython.rtyper.test.test_llinterp import interpret
+    import rpython.rlib.objectmodel
+    old = rpython.rlib.objectmodel.we_are_translated
+    rpython.rlib.objectmodel.we_are_translated = lambda: True
+    import rply
+    reload(rply.lexergenerator)
+    rpython.rlib.objectmodel.we_are_translated = old
 except ImportError:
-    py.test.skip("Needs RPython to be on the PYTHONPATH")
+    pytestmark = py.test.mark.skip("Needs RPython to be on the PYTHONPATH")
 
 from rply import LexerGenerator, ParserGenerator, Token
 from rply.errors import ParserGeneratorWarning
diff --git a/tox.ini b/tox.ini
index 539c54b..e689698 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,7 +5,8 @@ envlist = py26, py27, py33, py34, py35, pypy, docs
 deps = pytest
 # just running tox with PYTHONPATH=pypy tox fails, see
 # https://bitbucket.org/hpk42/tox/issue/146/setting-pythonpath-causes-tox-to-crash
-setenv = PYTHONPATH={env:PYPY_LOCATION}
+setenv =
+  py27,pypy: PYTHONPATH={env:PYPY_LOCATION}
 commands = py.test
 
 [testenv:docs]