It seems like vmail is very opinionated about line wrapping settings and somewhat difficult to override those opinions.
I have the following in my .vimrc (actually in my .vimrc.local; I use janus):
command! -nargs=* Plain set wrap linebreak nolist spell textwidth=0 wrapmargin=0
so that when I'm working with plain text, I can quickly switch to my preferred wrap settings. While this works great for Vimperator, txts and various markdown languages, I just can't get it to work with vmail for some reason.
Would you please let me know if there is any way to change this behaviour? I think that vmail is a really cool tool, and I would really love to use it, but this issue is pretty much a killer for me.
Thanks for your time and support
OK try installing Vmail version 2.4.7. This should let you apply those custom settings to Vmail's compose_message.txt window