Человек с форума зилога дал ссылку: http://www.z80.info/interrup2.htm
Consequently, contrary to stated documentation, bit zero is /not/ forced to zero, an IM2 interupt jumps to I*256+databus, not to (I*256+databus) AND 0xFFFE. If you want to reply on an even address, you must use hardware to supply an even address.