I wrote a user defined transformation in DB2 warehouse manager. It's effectively a user defined function. It has a varchar(4000) parameter and a varchar(4000) return type. I connected the transformation to a database table element hoping that what was returned from the function would populate one of the columns in the database. I getting an error that no column mapping have been defined. But when I define a java program in warehouse manager the column mapping tab just displays this message:

"Column mapping is not available for this step".

My question is how do I make column mappings available? Help!