Error encountered while integrating BPMS 6.1 with MS-SQL 2014

Issue

We are facing an error at server startup while using MS-SQL 2014 as Persistence DB for BPMS 6.1.We are using SQL-JDBC jar (sqljdbc41.jar) as our DB connectivity driver and EAP 6.4 as application server.

WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (ServerService Thread Pool -- 198) SQL Error: 206, SQLState: S0002
ERROR [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (ServerService Thread Pool -- 198) Operand type clash: nvarchar is incompatible with image
INFO  [org.hibernate.engine.jdbc.batch.internal.AbstractBatchImpl] (ServerService Thread Pool -- 198) HHH000010: On release of batch it still contained JDBC statements
ERROR [org.jboss.dashboard.error.ErrorManager] (ServerService Thread Pool -- 198) UNEXPECTED ERROR.
Error id='1441171146387'
Error date='2/9/15 10:49 AM'
com.microsoft.sqlserver.jdbc.SQLServerException: Operand type clash: nvarchar is incompatible with image
    at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:216)
    at com.microsoft.sqlserver.jdbc.SQLServerStatement.getNextResult(SQLServerStatement.java:1522)
    at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.doExecutePreparedStatement(SQLServerPreparedStatement.java:404)
    at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement$PrepStmtExecCmd.doExecute(SQLServerPreparedStatement.java:350)
    at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:5696)