EntityMalformedException when creating content with translatable Tags

Steps:

1. enable field translation for a content type
2. make at least one field in the content type translatable (Content types > Publishing options > "Enabled, with field translation")
3. enable "Taxonomy term" as a translatable type at admin/config/regional/entity_translation
4. add content of the type in step #1, adding tags
5. save content
6. observe error: "EntityMalformedException: Missing bundle property on entity of type node. in entity_extract_ids() (line 7647 of /home/pressflow/includes/common.inc)."

Note: either 1) disabling "Taxonomy term" as a translatable type or 2) changing all content type fields to not be translatable allows the new content to be saved without error.

Note: a warning is given when enabling Taxonomy terms as translatable for the first time: "The entities of type Taxonomy term do not define a valid path scheme: it will not be possible to translate them."

Seems like a common use case for Entity Translation, so it might be interference with another module of ours. But, has anyone seen this or is able to reproduce?

thank you!