Yes, the pensioner under age 65 can split pension with spouse. This is done by form T1032 in both pensioner and pensionee's tax return. First need to look at the worksheet for pensioner's field 314 of Schedule 1. If line A in the worksheet has an amount, then that amount is eligible for split.
There is a special treatment in part B of step 4 in form T1032 for the pension transferee, when the pension transferee's age is under 65. An in-eligible pension amount needs to be identified from line A, so that field 314 of Schedule 1 of the pension transferee can be correctly calculated. For in-eligible pension amount, check this CRA link.