If I put a name picker on an xpage that was navigated to from a view control using the open with 'XPage associated with the documents form' I get an error

and server Console shows error:
HTTP JVM: com.ibm.xsp.webapp.FacesServlet$ExtendedServletException: com.ibm.xsp.FacesExceptionEx: Unable to get document page name for null
However if I change the navigation of the view control to explicitly set the XPage to load, the picker works as expected, I am assuming that there is a 'pagename' type variable somewhere that is not set when using the auto-choose-xpage option.
The namepicker source is as follows
<xe:namePicker id="namePicker500" for="djextNameTextBox500">
<xe:this.dataProvider>
<xe:dominoNABNamePicker people="true" groups="false" nameList="people">
</xe:dominoNABNamePicker>
</xe:this.dataProvider>
</xe:namePicker>
<xe:djextNameTextBox id="djextNameTextBox500" multipleSeparator="," multipleTrim="true">
</xe:djextNameTextBox>