1 files changed, 7 insertions, 1 deletions
diff --git a/tox/__init__.py b/tox/__init__.py
index c17341d..baf651b 100644
--- a/tox/__init__.py
+++ b/tox/__init__.py
@@ -1,5 +1,5 @@
 #
-__version__ = '2.3.2'
+__version__ = '2.4.0.dev1'
 
 from .hookspecs import hookspec, hookimpl  # noqa
 
@@ -23,5 +23,11 @@ class exception:
         """ a directory did not exist. """
     class MissingDependency(Error):
         """ a dependency could not be found or determined. """
+    class MinVersionError(Error):
+        """ the installed tox version is lower than requested minversion. """
+
+        def __init__(self, message):
+            self.message = message
+            super(exception.MinVersionError, self).__init__(message)
 
 from tox.session import main as cmdline  # noqa