Problems with indexes in jbpm.history.hbm.xml

problem with indexes already indexed when running jbpm.oracle.create.sql:

create.jbpm.schema:
[sql] Executing resource: C:\SEAM\jbpm-4.0\db\schema.scripts\jbpm.oracle.create.sql
[sql] Failed to execute: create index IDX_HDETAIL_HACTI on JBPM4_HIST_DETAIL (HACTI_)
[sql] java.sql.SQLException: ORA-01408: such column list already indexed
[sql] Failed to execute: create index IDX_HDETAIL_HPROCI on JBPM4_HIST_DETAIL (HPROCI_)
[sql] java.sql.SQLException: ORA-01408: such column list already indexed
[sql] Failed to execute: create index IDX_HDET_HVAR on JBPM4_HIST_DETAIL (HVAR_)
[sql] java.sql.SQLException: ORA-01408: such column list already indexed
[sql] Failed to execute: create index IDX_HDET_HTASK on JBPM4_HIST_DETAIL (HTASK_)
[sql] java.sql.SQLException: ORA-01408: such column list already indexed
[sql] 76 of 80 SQL statements executed successfully