Working with non-core content (FAQs)

I have been using module_grants and workflow successfully on stories and pages. To standardise the content approach across the whole site I brought FAQ, Polls and Webforms 'into the fold'. To date I've only tested with FAQ, however this appears to have failed. My workflow is such that all users should be able to see content that is 'in draft' but only the author may edit it. However, with FAQs a non-author user does not see another user's draft content under "I can view" but does see it under "I can edit" although (s)he gets the "You are not authorised...." message if (s)he tries to open it.