Atmel slipped this 8-bit ATmega device in the what's new page recently, I don't recall noticing any prior datasheet versions being posted.
(file size: 19,219 KB, 217 pages, revision C, updated: 01/2013)
8-bit Micrcontroller, 17/18-bit ADC, 32/64k Flash Memory, 32-bit Math Extension Module, PGA, Power Supply and LIN Transceiver
â— 32bit math. extension module (+, "“, x, /)
â— Additional Math Extension Instruction set
Instruction Set Summary Pages 209 and 210 lists 38 instructions dedicated to "MATHS EXTENSION INSTRUCTIONS"
Searching for MATH or EXTENSION finds very little.