diff --git a/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php b/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
index d76710fba89cc..28a9e234c8121 100755
--- a/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
+++ b/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
@@ -261,7 +261,10 @@ public function guessPatternForConstraint(Constraint $constraint)
                 return new ValueGuess(sprintf('.{%s,%s}', (string) $constraint->min, (string) $constraint->max), Guess::LOW_CONFIDENCE);
 
             case 'Symfony\Component\Validator\Constraints\Regex':
-                return new ValueGuess($constraint->pattern, Guess::HIGH_CONFIDENCE );
+                $html_pattern = $constraint->getHtmlPattern();
+                return $html_pattern
+                    ? new ValueGuess($html_pattern, Guess::HIGH_CONFIDENCE)
+                    : null;
 
             case 'Symfony\Component\Validator\Constraints\Min':
                 return new ValueGuess(sprintf('.{%s,}', strlen((string) $constraint->limit)), Guess::LOW_CONFIDENCE);
diff --git a/src/Symfony/Component/Form/Tests/FormFactoryTest.php b/src/Symfony/Component/Form/Tests/FormFactoryTest.php
index b3dd506495771..189cdeec8cb32 100644
--- a/src/Symfony/Component/Form/Tests/FormFactoryTest.php
+++ b/src/Symfony/Component/Form/Tests/FormFactoryTest.php
@@ -528,7 +528,7 @@ public function testCreateBuilderUsesPatternIfFound()
                 ->method('guessPattern')
                 ->with('Application\Author', 'firstName')
                 ->will($this->returnValue(new ValueGuess(
-                    '/[a-z]/',
+                    '[a-z]',
                     Guess::MEDIUM_CONFIDENCE
                 )));
 
@@ -536,7 +536,7 @@ public function testCreateBuilderUsesPatternIfFound()
                 ->method('guessPattern')
                 ->with('Application\Author', 'firstName')
                 ->will($this->returnValue(new ValueGuess(
-                    '/[a-zA-Z]/',
+                    '[a-zA-Z]',
                     Guess::HIGH_CONFIDENCE
                 )));
 
@@ -544,7 +544,7 @@ public function testCreateBuilderUsesPatternIfFound()
 
         $factory->expects($this->once())
             ->method('createNamedBuilder')
-            ->with('firstName', 'text', null, array('pattern' => '/[a-zA-Z]/'))
+            ->with('firstName', 'text', null, array('pattern' => '[a-zA-Z]'))
             ->will($this->returnValue('builderInstance'));
 
         $builder = $factory->createBuilderForProperty(
diff --git a/src/Symfony/Component/Validator/Constraints/Regex.php b/src/Symfony/Component/Validator/Constraints/Regex.php
index 73f8b7b3323df..de05ba712ae24 100644
--- a/src/Symfony/Component/Validator/Constraints/Regex.php
+++ b/src/Symfony/Component/Validator/Constraints/Regex.php
@@ -12,6 +12,7 @@
 namespace Symfony\Component\Validator\Constraints;
 
 use Symfony\Component\Validator\Constraint;
+use Symfony\Component\Validator\Exception\ConstraintDefinitionException;
 
 /**
  * @Annotation
@@ -22,6 +23,7 @@ class Regex extends Constraint
 {
     public $message = 'This value is not valid.';
     public $pattern;
+    public $html_pattern = null;
     public $match = true;
 
     /**
@@ -39,4 +41,38 @@ public function getRequiredOptions()
     {
         return array('pattern');
     }
+
+    /**
+     * Sometimes, like when converting to HTML5 pattern attribute, the regex is needed without the delimiters
+     * Example: /[a-z]+/ would be converted to [a-z]+
+     * However, if options are specified, it cannot be converted and this will throw an Exception
+     * @return string regex
+     * @throws Symfony\Component\Validator\Exception\ConstraintDefinitionException
+     */
+    public function getNonDelimitedPattern() {
+        if (preg_match('/^(.)(.*)\1$/', $this->pattern, $matches)) {
+            $delimiter = $matches[1];
+            // Unescape the delimiter in pattern
+            $pattern = str_replace('\\' . $delimiter, $delimiter, $matches[2]);
+            return $pattern;
+        } else {
+            throw new ConstraintDefinitionException("Cannot remove delimiters from pattern '{$this->pattern}'.");
+        }
+    }
+
+    public function getHtmlPattern() {
+        // If html_pattern is specified, use it
+        if (!is_null($this->html_pattern)) {
+            return empty($this->html_pattern)
+                ? false
+                : $this->html_pattern;
+        } else {
+            try {
+                return $this->getNonDelimitedPattern();
+            } catch (ConstraintDefinitionException $e) {
+                // Pattern cannot be converted
+                return false;
+            }
+        }
+    }
 }
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/RegexValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/RegexValidatorTest.php
index 755f488577851..82e743c3c2c69 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/RegexValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/RegexValidatorTest.php
@@ -113,4 +113,64 @@ public function testConstraintGetDefaultOption()
 
         $this->assertEquals('pattern', $constraint->getDefaultOption());
     }
+
+    public function testNonDelimitedPattern() {
+        $constraint = new Regex(array(
+            'pattern' => '/^[0-9]+$/',
+        ));
+
+        $this->assertEquals('^[0-9]+$', $constraint->getNonDelimitedPattern());
+    }
+
+    public function testNonDelimitedPatternEscaping() {
+        $constraint = new Regex(array(
+            'pattern' => '/^[0-9]+\/$/',
+        ));
+
+        $this->assertEquals('^[0-9]+/$', $constraint->getNonDelimitedPattern());
+
+        $constraint = new Regex(array(
+            'pattern' => '#^[0-9]+\#$#',
+        ));
+
+        $this->assertEquals('^[0-9]+#$', $constraint->getNonDelimitedPattern());
+    }
+
+    public function testNonDelimitedPatternError() {
+        $constraint = new Regex(array(
+            'pattern' => '/^[0-9]+$/i',
+        ));
+
+        $this->setExpectedException('Symfony\Component\Validator\Exception\ConstraintDefinitionException');
+        $constraint->getNonDelimitedPattern();
+    }
+
+    public function testHtmlPattern() {
+        // Specified html_pattern
+        $constraint = new Regex(array(
+            'pattern' => '/^[a-z]+$/i',
+            'html_pattern' => '^[a-zA-Z]+$',
+        ));
+        $this->assertEquals('^[a-zA-Z]+$', $constraint->getHtmlPattern());
+
+        // Disabled html_pattern
+        $constraint = new Regex(array(
+            'pattern' => '/^[a-z]+$/i',
+            'html_pattern' => false,
+        ));
+        $this->assertFalse($constraint->getHtmlPattern());
+
+        // Cannot be converted
+        $constraint = new Regex(array(
+            'pattern' => '/^[a-z]+$/i',
+        ));
+        $this->assertFalse($constraint->getHtmlPattern());
+
+        // Automaticaly converted
+        $constraint = new Regex(array(
+            'pattern' => '/^[a-z]+$/',
+        ));
+        $this->assertEquals('^[a-z]+$', $constraint->getHtmlPattern());
+    }
+
 }