[Zope] MetaPublisher Image/File Field Problem

Hi, I have created a MetaPublisher which has several Image Fields and File Fields. I come into problems when I go to Edit entires and update an image field and or a File Field. I browse for a new image or file and even if I flag the check box "Select this box, if you want to delete the current image from this entry". This returns a Zope Error - <!-- Error type: while uploading an image Error value: None --> Has anyone using MetaPublisher come across this problem? Help appreciated. Regards, Michael Fox