Input enabled query issue with Characteristic relationship using Exits

Hi,

We have an input enabled query on a Infocube and in RSPLAN we have defined Characteristic Relationship using User exit . We have written this exit with reference to class CL_RSPLS_CR_EXIT_BASE. This exit works as expected because when we open a query we could see data which is fetched using teh Exit.(Let us say, in our real time cube we got value for product, but not for product group. we wanted to fill the product group after executing the planning function and before saving the data into Real time cube,when we open the Query in AFO(analysis for Office) we could see the product group data).

But the problem is the query which gets open up is not input enabled, we are not sure what is going wrong here....

Then we tried to test the input enabled query for the same infoprovider, so in RSPLAN we defined a Characteristic Relationship using DSO then in that case when we open the query in AFO the query is input enabled.

so we need help on what is missing in our case and why when we use Exit in Char. Relationship the query open in readonly mode ..

Thanks in advance...

A.Dinesh