ask and ye shall receive, so here's another question

So. I've always had a small problem with the typefaces that some Bujold list messages had been coming in, but I'd always thought it was a problem that couldn't be fixed. But I decided to ask why, on a supposedly plain mail email list I was getting different fonts from different people. Well, it turned out it was an easy fix.

So here I am to ask the DW and LJ equivalent. Ever since the last LJ "upgrade," everything is printed in Arial. I find sans serif fonts a real abomination to read. Is there a way to easily change *just* the typeface and nothing else?

If you have an easy answer, I genuinely want to know how to fix it. If it's more complicated, then consider it rhetorical [g].

About the only thing that doesn't come through in Arial is my actual composition of a post, which shows up in Courier. Go figure.