Latex export: Differing behavior for symbols in headlines

[Richard Lawrence <richard.lawrence@berkeley.edu>]

Dear Orgsters,

I am seeing differing behavior for how special symbols that appear in a
headline are exported to LaTeX, depending on whether I export an entire
Org document or just the current subtree.

I have, for example, a file that looks like this:

* Headline 1
** Headline 2, concerning $\alpha$ and $\beta$

If I export the whole document, the $'s around \alpha and \beta are
properly interpreted as math-mode delimiters, and Headline 2 becomes a
section title that looks exactly as I would expect.

If I export just Headline 2, however, the $'s are escaped, and show up
as literal '$' characters in the title of the exported document.

(I can't remove the $'s, because I am actually using some custom LaTeX
commands, not special symbols like \alpha and \beta that Org would
recognize as needing to be put in math mode.)

So, two questions:

1) Is this difference between whole-document vs. current-subtree export
the expected behavior?

2) If so, what's the right way to work around it?  If not, where should
I look to try and fix it?

(I am running the latest development version of Org.)

Thanks!

Best,
Richard