Hi Srihari,
Perhaps I haven't completely understood the problem, but...
You say that only SOME of the vendors use the Alternate UoM. Does that mean that sometimes you want the Declaration to be created in the Base UoM, and sometimes in the Alternate UoM? Or do you always want to use just one UoM for that product in GTS?
I can understand that, at the moment you always see the Base UoM quantity in the work-list, but I wonder why that confuses anyone - don't you always create the Declaration for the full quantity, whatever it is?
As part of a fix, you could over-write the quantity and UoM in the ERP BAdI /SAPSLL/IFEX_MM0A_R3 so that you get consistent data in GTS. Would that help?
Regards,
Dave