Riverbed - rbsh_process and rbsh_err_reason_failed

I am seeing a lot of below messages in the splunkd.log, for latter message I think I will have to re-write the regex. how do I fix the first warning message?

09-03-2013 11:54:03.773 -0400 WARN SearchOperator:kv - Invalid key-value parser, ignoring it, transform_name='rbsh_err_reason_failed'

09-03-2013 11:54:03.774 -0400 ERROR SearchOperator:kv - Cannot compile RE "(?Ss+){4}(?P<process>[^[]+)[(?P<pid>[^]:]+)" for transform 'rbsh_process': Regex: unrecognized character after (? or (?- 09-03-2013 11:54:03.774 -0400 WARN SearchOperator:kv - Invalid key-value parser, ignoring it, transform_name='rbsh_process'