Backward compatibility in Lenya 2.0 (Lenya 2.0 modules in Lenya 1.2.5)

Hi All

I am using lenya 2.0 for development of new site. I have developed few
modules for that. But I have my old site running on lenya 1.2.5 and cocoon
2.1.9. I want to have the new functionalities in my old site as well.

Is there any way that I can use new modules developed in lenya 2.0 in the
lenya websites based on lenya 1.2.5 and cocoon 2.1.9 ?

My specifications:
New: Lenya 2.0.2
Old: Lenya 1.2.5 and cocoon 2.1.9

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Regards
Sac