Drupal Community Portal

I upgraded to 7.12 and now when I try and save an article I get the error:
Fatal error: Call to undefined function taxonomy_field_insert() in /sites/all/modules/i18n/i18n_taxonomy/i18n_taxonomy.module on line 362
(It might not be an upgrade error... but I haven't done much else on my site.)
This is really crucial as users need to be able to add and save content, any help would be appreciated.
Thanks