Strange. I have tested current maser branch, and save operation did not work correctly. Database created with: CREATE DATABASE "hibtest" WITH OWNER "lukasz" ENCODING 'UTF8' LC_COLLATE = 'en_US.UTF-8' LC_CTYPE = 'en_US.UTF-8';.

In my opinion PostgreSQL JDBC driver causes hereby defect. Refer to linked bug report #5637: "JDBC driver method setClob() always uses getAsciiStream()".

Two possible workarounds for Hibernate users:

1. Annotate @Lob property with @Type(type="org.hibernate.type.StringClobType"). Note that org.hibernate.type.StringClobType is deprecated and new org.hibernate.type.MaterializedClobType does not fix reported case.
2. Provide custom PostgreSQL dialect as the one attached to JIRA ticket. By now I did not observe any disadvantages of using PreparedStatement#setCharacterStream() method in comparison to PreparedStatement#setClob(). Brett Meyer and Steve Ebersole should have a look. Moreover, after executing some basic load tests (persist CLOB followed by a single read), it seems that stream operations perform better.

Analogical issue rejected by Spring: https://jira.springsource.org/browse/SPR-7520.

Did my suggestions work for you?