I regularly correspond with someone who can only send and receive plain text, so I set Live Mail default to send plain text Quoted Printable (which prevents auto text wrapping) so that he can paste selections into other documents.

He sends very long replies, also as unwrapped plain text, but Windows Live Mail wraps the received mail at 76 characters in the reading pane and window.  This is irritating enough on a 30" monitor with 2500 horizontal pixels to play with, but devastatingly inconvenient when trying to paste into other documents, because text copied from the reading window retains the line breaks that Windows Live Mail officiously puts there.

How do I disable this anachronistic 'feature'?