[web2py] AttributeError: 'str' object has no attribute 'application'

[Johann Spies]

I have the following function in a module.  When I comment out the 'links' 
it works without a problem, but with the links active I get the error in 
the subject line:

def artikels(query = None):
    db = current.db
    if not query:
        query = db.akb_articles.id > 0 
                           
    links = [lambda row: A(T('show article'), _href = URL(r = request, c = 
'default',
                                                      f = 'show_akb_article'
,
                                                      args = row.id
                                                      ))]
    fields = [db.akb_articles.title, db.akb_articles.primaryauthor,
              db.akb_articles.authors,
              db.akb_articles.journal, db.akb_articles.pubyear, db.
akb_articles.url]    
    
    
    form = SQLFORM.grid(query,
                        fields = fields,
                        orderby = db.akb_articles.title,
                        maxtextlength = 90,
                        editable = False, deletable = False,
                        details = False,
                        searchable = False,
                        links = links,
                        ui = 'jquery-ui')
    return form

Why?  

Regards
Johann