[O] question/error concerning EXPORT_OPTIONS

[Rainer Stengele]

hi all,

for subtree specific html export options what's wrong with

** Subtree
      :PROPERTIES:
      :EXPORT_OPTIONS: <:t todo:t
      :END:
   - contents

I get this error:

or: Assertion failed: (functionp (symbol-value fun-var-sym)), nil

Which options are supported and how is the syntax for configuring?
I couldn't find an example.

Thanks,
Rainer