Hrm, yeah, I've also found that mail, hence why I linked it in the opening post. It seems that mail is mirrored a lot, and some provides timestamps, like this one: http://www.spinics.net/lists/linux-w.../msg28403.html.

The mail is from February 2009, so I figured it could've changed in one of the public releases since then. Anyway, thanks for the reply.

Edit: Oops, looks like I didn't look close enough. After inspecting the source to wl1251.h, there's a define that sets the preamble to long: http://tomoyo.sourceforge.jp/cgi-bin.../wl1251.h#L395.
So I guess one would have to recompile a patched version of the module.