A Error In Partition Table ,could You Tell Me ?

1 HIS_HTTP_LOG  a partition table
2 REL_HTTP_LOG  not a partition table,the same structure of HIS_HTTP_LOGï¼›
3 When HIS_HTTP_LOG doesn't exist any index
  the following executed succeed

  ALTER PARTITION SCHEME PS_HIS_HTTP_LOG NEXT USED [FG_03]
  ALTER PARTITION FUNCTION PF_HIS_HTTP_LOG() SPLIT RANGE ('20070331 23:59:59.997')
  ALTER TABLE TMP_HTTP_LOG SWITCH TO HIS_HTTP_LOG PARTITION 3

4 However when I added the index in HIS_HTTP_LOG and execute the step 3,It made error:
 a) CREATE INDEX IDX_HIS_HTTP_LOG_001 ON HIS_HTTP_LOG(USERID)ON PS_HIS_HTTP_LOG (STARTIME)
 b) ALTER PARTITION SCHEME PS_HIS_HTTP_LOG NEXT USED [FG_03]
    ALTER PARTITION FUNCTION PF_HIS_HTTP_LOG() SPLIT RANGE ('20070331 23:59:59.997')
    ALTER TABLE TMP_HTTP_LOG SWITCH TO HIS_HTTP_LOG PARTITION 3


=========================   Error messages================================================
"ALTER TABLE SWITCH statement failed. There is no identical index in source table 'TMP_HTTP_LOG SWITCH ' for the index 'IDX_HIS_HTTP_LOG_001' in target table 'HIS_HTTP_LOG' ."

When I added index in REL_HTTP_LOG ,it gave me the same error message

Could you tell me how can I solve the problem !