Parameters with multiple values

Hello,
We are trying to restrict a calculation view with HANA parameter which
gets the data from BO prompt. We succeed to send single value only in
the following way:

/********* Begin Procedure Script ************/
BEGIN
_date_list = SELECT DATE_SQL,
DATE_SAP
FROM
"_SYS_BI"."M_TIME_DIMENSION"
WHERE DATE_SAP
= :IP_REPORTING_DATE_LIST;

We cant send multiple single values from BO because it sends multiple
single values separated by comma and HANA needs one string with all the
values separated by the delimiter.

/********* Begin Procedure Script ************/
BEGIN
_date_list = SELECT DATE_SQL,
DATE_SAP
FROM
"_SYS_BI"."M_TIME_DIMENSION"
WHERE
(
(locate (:IP_REPORTING_DATE_LIST, ','||DATE_SAP||',') != 0 ) or

(locate (:IP_REPORTING_DATE_LIST, ','||DATE_SAP||')') != 0 ) or

(locate (:IP_REPORTING_DATE_LIST, '('||DATE_SAP||',') != 0 ) or

(locate (:IP_REPORTING_DATE_LIST, '('||DATE_SAP||')') != 0 )
);
We are on SPS5

Please help,
Thanks,
Amir