You should have received a T-slip (likely aT4A), you should also receive an RRSP Contribution Slip that says "transfer". You need to report them both and "designate" the contribution as a transfer.
Report the T-slip as normal. Your Total Income will reflect the amount of the lump-sum being transferred.
Report the RRSP contribution as a Transfer. The contribution will be deducted from income in the usual manner, but will not by itself reduce your remaining RRSP deduction limit.
