Well it seems moving to a CS5 machine won't help as it gives the same results there. Ideally you'd have the data inside Excel so it has one line (no line breaks) per field: Name, Function, Address, Address 2, ZIP, etc. etc. but since that's not the case we need to look at alternative methods.
I don't have Office here at home, but OpenOffice Calc lets me export to CSV files. They contain the data correctly, but with every line break inside the field as a character, at least when viewed inside Notepad. It should be possible to do a Find/Replace on that line break character to replace it with a character you won't normally see used (like the | ) or a combination of characters (like <|> ) which you can then re-replace after the merge. Just make sure there's enough room for every line inside the text frame before you start merging.
I'm no good with Office applications so maybe I'm missing something very obvious, like a method to break the data into columns… In any case I do hope you'll manage to get somewhere with this.
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