Fix for issue #180

library/Solarium/Core/Query/Helper.php

@@ -479,4 +479,17 @@ class Helper
         return $result;
     }
 
+    /**
+     * Filters control characters that cause issues with servlet containers.
+     *
+     * Mainly useful to filter data before adding it to a document for the update query.
+     *
+     * @param $data
+     * @return mixed
+     */
+    public function filterControlCharacters($data)
+    {
+        return preg_replace('@[\x00-\x08\x0B\x0C\x0E-\x1F]@', ' ', $data);
+    }
+
 }

tests/Solarium/Tests/Core/Query/HelperTest.php

@@ -404,4 +404,12 @@ class HelperTest extends \PHPUnit_Framework_TestCase
         );
     }
 
+    public function testFilterControlCharacters()
+    {
+        $this->assertEquals(
+            'my string',
+            $this->helper->filterControlCharacters("my\x08string")
+        );
+    }
+
 }