diff --git a/src/cairo-pdf-interchange.c b/src/cairo-pdf-interchange.c
index 7d8981b09..0f896d351 100644
--- a/src/cairo-pdf-interchange.c
+++ b/src/cairo-pdf-interchange.c
@@ -1666,7 +1666,8 @@ iso8601_to_pdf_date_string (const char *iso)
     if (strlen (p) < 3)
 	goto finish;
 
-    strncat (buf, p + 1, 3);
+    strncat (buf, p + 1, 2);
+    strcat (buf, "'");
 
   finish:
     strcat (buf, ")");