diff --git a/src/IDF/Form/UploadArchiveHelper.php b/src/IDF/Form/UploadArchiveHelper.php
index 907ca50..50f8aad 100644
--- a/src/IDF/Form/UploadArchiveHelper.php
+++ b/src/IDF/Form/UploadArchiveHelper.php
@@ -102,6 +102,12 @@ class IDF_Form_UploadArchiveHelper
                 }
             }
 
+            // FIXME: remove this once we allow more than six labels everywhere
+            if (count($entry['labels']) > 6) {
+                throw new Pluf_Form_Invalid(
+                    sprintf(__('The entry %s in the manifest has more than the six allowed labels set.'), $entry['name']));
+            }
+
             $this->entries[$entry['name']] = $entry;
         }
 
diff --git a/src/IDF/templates/idf/faq-archive-format.html b/src/IDF/templates/idf/faq-archive-format.html
index af167fb..7952bb5 100644
--- a/src/IDF/templates/idf/faq-archive-format.html
+++ b/src/IDF/templates/idf/faq-archive-format.html
@@ -85,8 +85,12 @@ This is the DTD for the format:
 </pre>
 
 <p>
-The format is more or less self-explaining, all fields map to properties of a single download.
-One special element has been introduced though, <code>replaces</code>. If this optional element
+The format is more or less self-explaining, all fields map to properties of a single download. Note
+that there is a limit of <strong>six</strong> labels that you can attach to a download, similar to
+what the regular file upload functionality allows.
+</p> 
+
+<p>One special element has been introduced and this is named <code>replaces</code>. If this optional element
 is given, InDefero looks for a file with that name in the project and acts in one of the following
 two ways:
 </p>