[PLUG] Strange Emacs Behavior

[Rich Shepard]

   Before you vim-ers tell me that emacs always behaves strangely ... stop!
This is not an editor war story.

   I'm writing a LaTeX script (for PSTricks) and the letter following an
underscore character is also lowered and smaller than the rest of the text.
I have a screenshot that may be stripped off this message, but can be sent
privately. Never have seen this before. It's more of a distraction than
anything else, but if there's an explanation I'd sure like to learn what
that is.

   Any ideas?

Rich