For the impatient:
Patch for Pine 4.60 and 4.61, 4.63, 4.64
RedHat and Debian packages
Pine source
FAQ on patching pine

I use Pine as my email client, and I really like it. It’s fast, simple, full-featured, and very keyboardable. However, nothing’s perfect, even Pine.

Pine 4.60 added support for flowed text a la RFC2646, which is great. If you want, you can tell it not to send flowed text…but there’s no way to tell it not to display flowed text. This patch adds that option.

There are also pre-built packages with this patch, thanks to Chuck Wolber, and instructions on building Pine from source. Scroll to the bottom.