This utility should be used with "IL-2 Sturmovik" (NOT with "IL-2 Sturmovik: Forgotten battles")
In the installation directory find file rts.dll (981729 bytes) and rename it to rts.dll_original or something similar. Copy spy.dll & rts.dll from zip to that directory.
Start game. After finishing you will find directory C:\dump\IL2_dump.
Java classfiles are here. To disable dumping just rename your backup rts.dll_original to rts.dll. That's all