This code will preserve the email formatting when forwarding onto others .
If you use the <#fwd> tag in the history list (history.html). The default tag would look like:
<#fwd image=images/forward_email.gif border=0>
But that will only include the history items that have a type that matches the Email Sent type on Admin...Site Settings...Misc Settings...Type Settings - if you want to include additional types, just add type="another type" parameters to the <#fwd tag.