datestyle GUC broken in HEAD?

(perhaps with the committing and then reversing of the custom variables
patch?)
postgres=# show datestyle;DateStyle 
-----------ISO, DMY
(1 row)
postgres=# set datestyle='DMY,ISO';
SET
postgres=# show datestyle;DateStyle 
-----------ISO, DMY
(1 row)
--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com
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