diff --git a/.gitattributes b/.gitattributes
index 7c79f1b..fcadb2c 100755
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,2 +1 @@
-[text]
-	eol = lf
+* text eol=lf
diff --git a/.gitignore b/.gitignore
index 4b08d9f..88a89cf 100755
--- a/.gitignore
+++ b/.gitignore
@@ -4,5 +4,6 @@
 # Composer.
 vendor
 composer.lock
+composer.phar
 
 tests/assets/test.json
diff --git a/src/IMT.php b/src/IMT.php
index 4d9b287..b7717e0 100644
--- a/src/IMT.php
+++ b/src/IMT.php
@@ -1,5 +1,5 @@
 <?php namespace Locker\XApi;
 
 class IMT extends RegexpAtom {
-  protected static $pattern = '/^(application|audio|example|image|message|model|multipart|text|video)(\/[-\w\+]+)(;\s*[-\w]+\=[-\w]+)*;?$/';
+  protected static $pattern = '/^((application|audio|example|image|message|model|multipart|text|video)(\/[-\w\+\.]+)(;\s*[-\w]+\=[-\w]+)*;?)$/';
 }
diff --git a/tests/assets/test.json b/tests/assets/test.json
index 119cf0b..9d4e389 100644
--- a/tests/assets/test.json
+++ b/tests/assets/test.json
@@ -10,5 +10,14 @@
     },
     "object": {
         "id": "http:\/\/localhost\/moodle\/mod\/quiz\/attempt.php?attempt=48"
-    }
+    },
+    "attachments": [{
+      "contentType": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+      "usageType": "http://www.example.com",
+      "display": {},
+      "description": {},
+      "length": 100,
+      "sha2": "9cfe7faff7054298ca87557e15a10262de8d3eee77827417fbdfea1c41b9ec23",
+      "fileUrl": "http://www.example.com"
+    }]
 }