Pentomino Sudoku

Rules:

Place the numbers from 1 to 9 exactly once in every row, column, and box.

Place exactly one of each of the 12 pentomino shapes in the grid. Pentominos cannot overlap, but may touch. A cell with a clue indicates which pentomino must occupy that cell, and a pentomino may contain at most one clue. A clue outside the grid indicates the sum of numbers not in pentominos in the row or column.

Each pentomino must satisfy at least one of the two conditions:

Whisper:

Adjacent numbers in the pentomino must differ by at least 5.

Region Sums:

The sum of the numbers in the pentomino is the same in each box of the sudoku that the pentomino is in. If a pentomino is wholly contained in a single box, this condition is invalid.