Hi,
When you define/edit the data connection, you want to press the formula
button (fx) on the right of the Attachment name box.  Then in there
press the "Insert Function" button and choose "concat" from the list.
This will then prompt you to double click to add fields, you can also
replace the "double click to insert field" text with your own quoted
text to separate your fields if you wish.  There does not seem to be a
limit to the number of items you can include in a single concat
function, so you can place as many commas in there as you like so that
you can concatenate lots of fields or text....
hope this helps
cheers
Bruce