diff --git a/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php b/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
index 16948f6769..8fe5eecc4a 100644
--- a/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
+++ b/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
@@ -31,7 +31,7 @@ class StateMachineValidator implements DefinitionValidatorInterface
             // Make sure that each transition has exactly one FROM
             $froms = $transition->getFroms();
             if (1 !== count($froms)) {
-                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one input. But the transition "%s" in StateMachine "%s" has %d inputs.', $transition->getName(), $name, count($transition->getTos())));
+                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one input. But the transition "%s" in StateMachine "%s" has %d inputs.', $transition->getName(), $name, count($froms)));
             }
 
             // Enforcing uniqueness of the names of transitions starting at each node