Lotus Notes 7 and 8.5 JVM compatibility

Greetings all

i developed an application on Lotus notes 8.5 using Java script libraries. I had to work on 8.5 since its JVM was updated. There are few APIs that I use and donot work on JRE 4, thats why i made this application on 8.5 lotus notes.

Now my problem: when i run my application on notes 7 or 6.5 it doesnt work however it sure works on 8.5. is there any way that i can solve this compatibility issue? please help