Cannot translate existing (bootstrap) documents

Steps to reproduce
1) Login Go Green with admin/admin
2) Open Hippo Duurzaam / Evenementen / 2013 / 09 / SJF...
3) Translate / French
4) Enter a folder name and new document name
5) Click OK
Expected: Translated Document opened
Actual: An error occured, please retry

Stacktrace:
javax.jcr.version.VersionException: Unable to perform operation. Node is checked-in.
at org.apache.jackrabbit.core.ItemValidator.checkCondition(ItemValidator.java:284)
at org.apache.jackrabbit.core.ItemValidator.checkModify(ItemValidator.java:248)
at org.apache.jackrabbit.core.NodeImpl.checkSetProperty(NodeImpl.java:983)
at org.apache.jackrabbit.core.NodeImpl$SetPropertyOperation.perform(NodeImpl.java:2043)
at org.apache.jackrabbit.core.NodeImpl$SetPropertyOperation.perform(NodeImpl.java:1998)
at org.apache.jackrabbit.core.session.SessionState.perform(SessionState.java:216)
at org.apache.jackrabbit.core.NodeImpl.setProperty(NodeImpl.java:1920)
at org.apache.jackrabbit.core.NodeImpl.setProperty(NodeImpl.java:1890)
at org.hippoecm.repository.decorating.NodeDecorator.setProperty(NodeDecorator.java:155)
at org.hippoecm.repository.translation.impl.TranslationWorkflowImpl.addTranslation(TranslationWorkflowImpl.java:100)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.hippoecm.repository.impl.WorkflowManagerImpl$WorkflowInvocationHandler.invoke(WorkflowManagerImpl.java:524)
at com.sun.proxy.$Proxy86.addTranslation(Unknown Source)
at org.hippoecm.frontend.translation.workflow.TranslationWorkflowPlugin$TranslationAction.executeNonAvailableTranslation(TranslationWorkflowPlugin.java:316)
at org.hippoecm.frontend.translation.workflow.TranslationWorkflowPlugin$TranslationAction.execute(TranslationWorkflowPlugin.java:267)
at org.hippoecm.frontend.translation.workflow.TranslationWorkflowPlugin$TranslationAction.execute(TranslationWorkflowPlugin.java:222)
at org.hippoecm.addon.workflow.StdWorkflow.execute(StdWorkflow.java:222)
at org.hippoecm.addon.workflow.StdWorkflow.execute(StdWorkflow.java:208)
at org.hippoecm.addon.workflow.StdWorkflow.invokeWorkflow(StdWorkflow.java:241)
at org.hippoecm.addon.workflow.AbstractWorkflowDialog.onOk(AbstractWorkflowDialog.java:54)
at org.hippoecm.frontend.dialog.AbstractDialog.handleSubmit(AbstractDialog.java:522)
at org.hippoecm.frontend.dialog.AbstractDialog$2.onSubmit(AbstractDialog.java:280)
at org.hippoecm.frontend.dialog.ButtonWrapper$1.onSubmit(ButtonWrapper.java:79)
at org.apache.wicket.ajax.markup.html.form.AjaxButton$1.onSubmit(AjaxButton.java:108)
at org.apache.wicket.ajax.form.AjaxFormSubmitBehavior$1.onSubmit(AjaxFormSubmitBehavior.java:179)