diff --git a/src/Symfony/Component/Process/Process.php b/src/Symfony/Component/Process/Process.php
index b8d863af50..acc9a3e6c0 100644
--- a/src/Symfony/Component/Process/Process.php
+++ b/src/Symfony/Component/Process/Process.php
@@ -1108,11 +1108,13 @@ class Process
      *
      * This content will be passed to the underlying process standard input.
      *
-     * @param string|null $input The content
+     * @param mixed $input The content
      *
      * @return self The current Process instance
      *
      * @throws LogicException In case the process is running
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public function setInput($input)
     {
diff --git a/src/Symfony/Component/Process/ProcessBuilder.php b/src/Symfony/Component/Process/ProcessBuilder.php
index 189ab8a3d1..1e3833774e 100644
--- a/src/Symfony/Component/Process/ProcessBuilder.php
+++ b/src/Symfony/Component/Process/ProcessBuilder.php
@@ -167,13 +167,13 @@ class ProcessBuilder
     /**
      * Sets the input of the process.
      *
-     * Deprecation: As of Symfony 2.5, this method only accepts string values.
-     *
-     * @param string|null $input The input as a string
+     * @param mixed $input The input as a string
      *
      * @return ProcessBuilder
      *
      * @throws InvalidArgumentException In case the argument is invalid
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public function setInput($input)
     {
diff --git a/src/Symfony/Component/Process/ProcessUtils.php b/src/Symfony/Component/Process/ProcessUtils.php
index 0f4cb89e6b..dd0a74373c 100644
--- a/src/Symfony/Component/Process/ProcessUtils.php
+++ b/src/Symfony/Component/Process/ProcessUtils.php
@@ -83,6 +83,8 @@ class ProcessUtils
      * @return string The validated input
      *
      * @throws InvalidArgumentException In case the input is not valid
+     *
+     * Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.
      */
     public static function validateInput($caller, $input)
     {
@@ -95,6 +97,8 @@ class ProcessUtils
             }
             // deprecated as of Symfony 2.5, to be removed in 3.0
             if (is_object($input) && method_exists($input, '__toString')) {
+                trigger_error('Passing an object as an input is deprecated since version 2.5 and will be removed in 3.0.', E_USER_DEPRECATED);
+
                 return (string) $input;
             }
 
diff --git a/src/Symfony/Component/Process/Tests/AbstractProcessTest.php b/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
index 5bfd1a8692..345ae221c9 100644
--- a/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
+++ b/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
@@ -229,7 +229,24 @@ abstract class AbstractProcessTest extends \PHPUnit_Framework_TestCase
             array(null, null),
             array('24.5', 24.5),
             array('input data', 'input data'),
-            // to maintain BC, supposed to be removed in 3.0
+        );
+    }
+
+    /**
+     * @dataProvider provideLegacyInputValues
+     */
+    public function testLegacyValidInput($expected, $value)
+    {
+        $this->iniSet('error_reporting', -1 & ~E_USER_DEPRECATED);
+
+        $process = $this->getProcess('php -v');
+        $process->setInput($value);
+        $this->assertSame($expected, $process->getInput());
+    }
+
+    public function provideLegacyInputValues()
+    {
+        return array(
             array('stringifiable', new Stringifiable()),
         );
     }