Index: sites/all/modules/contrib/gelf/gelf.module
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- sites/all/modules/contrib/gelf/gelf.module	(revision 38835)
+++ sites/all/modules/contrib/gelf/gelf.module	(revision )
@@ -78,7 +78,7 @@
     $username = isset($entry['user']->name) ? $entry['user']->name : variable_get('anonymous', t('Anonymous')); 
     $message = strip_tags(is_array($entry['variables']) ? strtr($entry['message'], $entry['variables']) : $entry['message']);
     $short_msg_length = 100;
-    if (drupal_strlen($message) > $short_msg_length) {
+    if (gelf_strlen($message) > $short_msg_length) {
       $short_message = preg_replace('/\s+?(\S+)?$/u', '', drupal_substr($message, 0, $short_msg_length));
     }
     else {
@@ -135,4 +135,23 @@
     '#default_value' => variable_get('gelf_port', 12201),
   );
   return system_settings_form($form);
+}
+
+/**
+ * Copy of drupal_strlen to avoid fatal errors if watchdog is called before full bootstrap.
+ *
+ * Count the amount of characters in a UTF-8 string. This is less than or
+ * equal to the byte count.
+ *
+ * @ingroup php_wrappers
+ */
+function gelf_strlen($text) {
+  global $multibyte;
+  if ($multibyte == UNICODE_MULTIBYTE) {
+    return mb_strlen($text);
+  }
+  else {
+    // Do not count UTF-8 continuation bytes.
+    return strlen(preg_replace("/[\x80-\xBF]/", '', $text));
+  }
 }
\ No newline at end of file