11.2.0.4 on Solaris ORA-1466 (RO Tx began Last DDL: s^F...) showing in alert log

Getting the following messages in alert log for 11.2.0.4 supporting EBS 11.5.10.2:

Tue Jun 30 05:04:39 2015
ORA-1466 (RO Tx began: 06/30/2015 08:59:16, Last DDL: s^F^^
^E'2015 09:04:36, Curr Time: 06/30/2015 09:04:38)
Tue Jun 30 05:05:18 2015
ORA-1466 (RO Tx began: 06/30/2015 08:59:16, Last DDL: s^F^^
^F^R2015 09:05:01, Curr Time: 06/30/2015 09:05:17)
Tue Jun 30 05:05:56 2015
ORA-1466 (RO Tx began: 06/30/2015 08:59:16, Last DDL: s^F^^
^F82015 09:05:01, Curr Time: 06/30/2015 09:05:55)
Tue Jun 30 05:08:45 2015
Tue Jun 30 08:01:49 2015

I found a discussion on MOSC that stated this could be the result of the UNDO not being large enough. Is there any other possible cause for this you may be able to assist with?