BIP (OBIEE 11.1.1.7): CLOB related issue in Data Model

Hello,

Trying to create a data model where the query has a CLOB column. We typically use following type of code :

REPLACE(dbms_lob.substr(table.column_name,50,1),chr(10),' ')

This allows us to print only leading few characters from the CLOB column.

With BI Publisher, this code when included in the query results in error:

"Failed to Load XML", An invalid character was found in text content.

Any idea why this doesn't work? The data in that CLOB is some text/instructions typed by user. The SQL works in SQL Developer and Oracle Reports but does not work in BI Publisher.