Hi Bala,
Both part numbers mentioned by you are valid and correct. The first part number "CP-7945G-CCME" is a bundle part number for the Phone and CME license while the second way of ordering is also valid where you configure the CME license part number under the pone in DCT.
There is not good or bad way of ordering in this case.
But given a choice I'll go for the second way of ordering since in DCT this method provides me the services part codes.
-> Sushil