[vile] nohl inside define-mode

[lists-vile]

I work with files for which I want to specify some alternate settings. Here is
a snippet from my .vilerc file:

define-mode sdlmode
~with define-submode sdlmode
    suffixes '\.pr$'
    nohl
    ts=2
    sw=2
~endwith

If I open a C file vile performs syntax highlighting as expected. When
I open a .pr later and switch back to the C file highlighting in the C file is
disabled. I thought from the help documentation that the hl setting was local
to the buffer if specified?

I'm using 9.8e but I believe it happened with 9.7 as well.