Biztalk 2009/2010 – Converting flat file to X12 file

Hello all, hopefully someone can help me out here, I’ve been scouring the internet for days and haven’t found an answer.

What I’m looking to do is take a flat file (delimited or fixed-width), and convert it to x12 format.  We’ve already got the maps and schemas created to do it, and it works fine, with one exception, batching.  We can get Biztalk to do the conversion and spit out an X12 file, but it will create one X12 file for each record, and we have not found a way to batch them together in a way that will translate properly to the EdiSend pipeline and output a batched x12 file.

If anyone has any answers, references, ideas, ANYTHING is useful at this point. 

Just FYI we are currently working on Biztalk 2010, but anything that is still applicable in BT2009 should be fine.