Replacing GLT0 table by FAGLFLEXT

Dear ABAP Experts,

I am working in New GL SAP implementation project.

In this project. My Client Upgrding the SAP R/3 4.7 by ECC6.0. After Upgrade we are implementing the New GL activation.

After New GL Activation SAP Replaces GLT0 table by FAGLFLEXT.

I want to Replace GLT0 table by FAGLFLEXT table in all the Z-Programs. Before that i checked the FAGLFLEXT table, it contains all the fields in GLT0 and additional fields.

The Difference is the Key fields in the GLT0 table is not same as the Key fields in FAGLFLEXT table.

So i want to know if i replace the table and fields from GLT0 to FAGLFLEXT. Will it have any problem? if it has any problem how i have to solve this problem.

Thanks & Regards,

Ashok.