Thanks a lot for your suggestions, Judy. I had seen your posts about this problem on the other forum.
Unfortunately, the data is stored in a text field, not multivalue.
The big problem is not the line breaks, but the wrapping.
What works, but seems primeval, is in the source doc field replacing @NewLine with <BR>, and replacing " " with some character (I use ^^). Then in the Xpage I use a computed field rendering html (that recognizes the <BR>'s and gives me the line breaks), and do value.replace("^^", " ").
Really, it seems ridiculous to me to have to resort to such lengths, but it's the only combination, out of the zillions I've tried, that works.