Dummy relation field kills other field entries

When creating nodes with the dummy relation fields on them, content from the body field is erased upon node save.

Steps to reproduce:

* Clean Drupal install (standard installation), plus most recent release Relation module. (Have also tried latest Git clone.)
* Enable all three relation modules.
* Add a new relation type. Have it relate all node bundles, leave other options at default.
* Add the dummy relation field to Articles.
* Add a new article, with title Example article.
* Add a new article. Give it a body and enter "Example article" in the dummy relation field.
-> Upon save, there is no body visible on the article view page.
-> When editing the node, the body field is empty (indicating that the body was never saved).

Same thing happens when adding another article, also relating to the Example article.