Both Pentium M Dothan and Core Duo have the say number of pins ( 479 on socket 479 ) but Intel put the pins at different places.

Even if they are pin-to-pin compatible, no BIOS upgrade are available and the old chipset ( i915 XX ) is not compatible with the Core Duo who uses i945 XX chipset.

Voltage of both processor is not the same also :
27 Watt for Dothan
35 Watt for Yonah