Using 'Drill Through' functionality to view data against mapped accounts

If I have following 5 accounts in BW: ACCT_1, ACCT_2, ACCT_3, ACCT_4 & ACCT_5 and while importing data, these accounts are mapped in the following manner to two new BPC Accounts (P_ACCT, Q_ACCT):

1. ACCT_1 + ACCT_2 +ACCT_3 --> P_ACCT
2. ACCT_4 +ACCT_5 --> Q_ACCT

Then using Drill through in EPM 10 reports can we drill back from P_ACCT & Q ACCT to the underlying 5 BW accounts (ACCT_1, ACCT_2, ACCT_3,  ACCT_4 & ACCT_5) to view data against each of these 5 accounts?