What you could do is use MIME encapsulation it store the NOTES Formating – but this would be an SMTP server change and would effect all from this server – hense the question. Then exchange might be able to use the encapsulation to view correctly.

Message Content Specifies how Domino structures the MIME content of messages when converting Notes rich text messages before sending them over SMTP. Choose one:

Convert from Notes to plain text – (default) Domino converts the text in a Notes rich text document to plain text. If the message contains file attachments or images, Domino includes these as attachments by creating a multipart/mixed MIME message with the images and attachments following the text/plain part. Use this option in organizations that send most of their outbound mail to mail systems that are unable to handle MIME messages containing multiple text parts (for example, messages with the multipart/alternative structure that includes text/plain and text/html parts.
Convert from Notes to HTML – Domino converts the text in a Notes rich text document to HTML. If the message contains file attachments, Domino creates a multipart/mixed MIME message and includes the attachment in that part. If the message contains images, Domino includes the images in the message body by creating a multipart/related part.
Convert from Notes to Plain Text and HTML – Domino converts the text in a Notes rich text document to both plain text and HTML by creating a multipart/alternative body part that contains both the text/plain and text/html parts. If the message contains file attachments, Domino creates a multipart/mixed MIME message and includes the attachment in that part. If the message contains images, Domino creates a multipart/related part and includes the image in that part along with the text parts.
Create multi-part alternative including conversion and encapsulation - Domino converts Notes rich text messages as in the previous option and create an additional file attachment that contains a Notes database with the original message in it.