At last I've crossflashed my DRW-22B3L into iHAP422 W with firmware dump that was kindly provided by Blu from iXtreme forums.
Also I've dumped iHAP122 W firmware for anyone who will need it.
Here are both dumps:
iHAP122 W LL06 - http://www72.zippyshare.com/v/25535959/file.html
iHAP422 W 7L14 - http://www72.zippyshare.com/v/93217057/file.html
Mr, CVS, I know these dumps will be nice addition to your collection
Now only iHAP222 W 7L05 dump left to found to complete iHAPx22 W unscrambled firmwares collection
Also, here are official executables of "W" pata drives which are not present on FirmwareHQ - iHAP222 W, iHAP322 W and iHAP422 W firmwares: http://www72.zippyshare.com/v/5646763/file.html
It would be great if these firmwares were added to FirmwareHQ database.
PS: If somebody will extract correct iHAP222 W firmware from executable, it would be just great. Or patch the official flasher to skip drive checking - unfortunately I lack necessary knowledge and experience to make it myself. I'm ready to try to experiment with the real drive.