The options field keeps the serialized array of found UIDs of an OAI set. With 6-digit UIDs it is only possible to have about 6500 objects in an OAI set. In this case the serialized array is cutted an the OAI plugin will fail with an exception. Before commitpull/452/head
443aaff2cbthis field was textlong which might be really too long. This patch changes the field to mediumtext wich should be able to keep about 1.6 million objects.