sendmail form that preserves "extra" spaces

I am looking for a WordPress 2.9+ plugin, such as a sendmail form or contact form, that will preserve (not strip out) extra spaces in a message. Most forms include code to strip out these spaces, but we want an option to preserve them.

We want to provide an online entry form for a poetry contest. We want to preserve all spaces and line breaks exactly as the contestant entered them. For example, we want to preserver the spaces and line breaks I the following text, which is in the shape of a Christmas tree:

s
i t
r m
h t a
c r s
e
e