How to Mask Data in Data Mask Transform in selective positions?

Hi ,

I tried Data Mask Transform and achieve the following result

Ex: if Bank acc num is :2323232323 then masked output is 2323XXXXXX or XXXXXX2323 based on Start and End Position and Unmasked length.

But i want output like 23XXX32XXX is it possible to achieve this using Data Mask Transform ?

Please give your inputs.

Thanks,

Chandra