Seems that IDM already aware with the simple hack techniques that been introducer earlier, hence the latest IDM released will not 'lost' to the techniques.
However from ONHAX site I get new crack that can repair the fake serial number 'inflection'
Using the crack, user can fix the fake serial number.
Then just hit the Crack & Activate button
Very simple to use
installer can be downloaded from IDM page
**tested with version 6.15 final on 08 MARCH 2013
download installer IDM 6.15 4shared
download Crack from 4 shared