diff --git a/src/main/python/fysom/__init__.py b/src/main/python/fysom/__init__.py
index 102dd06..191850e 100644
--- a/src/main/python/fysom/__init__.py
+++ b/src/main/python/fysom/__init__.py
@@ -192,7 +192,7 @@ def _apply(self, cfg):
              >> Prepares the event to state transitions map.
         '''
         init = cfg['initial'] if 'initial' in cfg else None
-        if self._is_base_string(init):
+        if self._is_base_string_or_int(init):
             init = {'state': init}
 
         self._final = cfg['final'] if 'final' in cfg else None
@@ -207,7 +207,7 @@ def add(e):
                 Adds the event into the machine map.
             '''
             if 'src' in e:
-                src = [e['src']] if self._is_base_string(
+                src = [e['src']] if self._is_base_string_or_int(
                     e['src']) else e['src']
             else:
                 src = [WILDCARD]
@@ -357,12 +357,12 @@ def _change_state(self, e):
         if hasattr(self, fnname):
             return getattr(self, fnname)(e)
 
-    def _is_base_string(self, object):  # pragma: no cover
+    def _is_base_string_or_int(self, object):  # pragma: no cover
         '''
             Returns if the object is an instance of basestring.
         '''
         try:
-            return isinstance(object, basestring)
+            return isinstance(object, basestring) or isinstance(object, int)
         except NameError:
             return isinstance(object, str)