[web2py] "function ... is not JSON serializable" error when rendering db row as JSON

[Amnon Khen]

Dear web2py folks,

I have a controller that fetches a record from the DB (I'm using
GAE).

   def event():
      id=request.args[0]
      myrow = db.event[id]
      return dict(myrow = myrow)

What I try to render the result as JSON, I get the following error
(trace starts from generic.json view)

  File "C:\Users\Hampi\git\skeduk\web2py\gluon\serializers.py", line
30, in custom_json
    raise TypeError(repr(o) + " is not JSON serializable")
  TypeError: <function <lambda> at 0x05EA7A30> is not JSON
serializable

When I try to render the same controller's result using the
generic.xml view, the rending is done OK, nad I see that "function
<lambda> at 0x05EA7A30" is the row's "update_record" method.

Why are my object's methods being serialized?
Is this a bug in the custom_json function in serializers.py?

Thanks for you help,
   Amnon Khen