Good day, I've been using Zope and Python for about two weeks now, and I've been able to figure everything for myself so far (with the help of this list and other docs, of course). I've figured how to work around the following problem, but I don't understand what causes the error in the first place. I have not been able to find an instance of the error type "Bad request" in this group or searching zope.org. The problem comes up when trying to call a zsql method with implicit argument passing. The zsql method (insertOccurences) declares the two arguments 'occurence' and 'problemID'. The calling dtml is as follows: <dtml-let problemID="radarDBSessionData.getSessionData().get('insertedProblemID')"> <dtml-in occurences> <dtml-let occurence=sequence-item> <dtml-call insertOccurence> </dtml-let> </dtml-in occurences> </dtml-let> On running this, Zope returns the following error: Error Type: Bad Request Error Value: ['occurence', 'problemID'] Traceback (innermost last): File D:\pf2\radar\lib\python\ZPublisher\Publish.py, line 223, in publish_module File D:\pf2\radar\lib\python\ZPublisher\Publish.py, line 187, in publish File D:\pf2\radar\lib\python\Zope\__init__.py, line 221, in zpublisher_exception_hook (Object: Traversable) File D:\pf2\radar\lib\python\ZPublisher\Publish.py, line 171, in publish File D:\pf2\radar\lib\python\ZPublisher\mapply.py, line 160, in mapply (Object: selectProblemPage) File D:\pf2\radar\lib\python\ZPublisher\Publish.py, line 112, in call_object (Object: selectProblemPage) File D:\pf2\radar\lib\python\OFS\DTMLMethod.py, line 189, in __call__ (Object: selectProblemPage) File D:\pf2\radar\lib\python\DocumentTemplate\DT_String.py, line 538, in __call__ (Object: selectProblemPage) File D:\pf2\radar\lib\python\DocumentTemplate\DT_Let.py, line 147, in render (Object: problemID="radarDBSessionData.getSessionData().get('insertedProblemID')") File D:\pf2\radar\lib\python\DocumentTemplate\DT_In.py, line 717, in renderwob (Object: occurences) File D:\pf2\radar\lib\python\DocumentTemplate\DT_Let.py, line 147, in render (Object: occurence=sequence-item) File D:\pf2\radar\lib\python\Shared\DC\ZRDB\DA.py, line 476, in __call__ (Object: insertOccurence) File D:\pf2\radar\lib\python\Shared\DC\ZRDB\Aqueduct.py, line 150, in _argdata (Object: insertOccurence) Bad Request: (see above) My workaround is to pass the arguments explicitely, i.e. <dtml-call "insertOccurence(occurence=_.getitem('occurence'),problemID=_.getitem('problemID'))"> But I think that this should be unnecessary. Anybody has an explanation for the error? I admit that I may still have some fundamental misunderstanding of the Zope namespace and of method calling (for example, why is it necessary to include _=_ in the arguments list to get the namespace in a script, even after declaring the binding?), so maybe the reason will be obvious to some of you Python/Zope Gods. Bonus question: The 'occurences' (plural) variable above was produced by using the :records type qualifier on a form (great feature by the way). I have not been able to figure the type of the returned object, and I am curious. If I iterate over the list, the sequence-item has the keys() method, but trying to set a key in a script (x['thekey']=y) produces the error ("object does not support item assigment"). Similarly, I can use getattr on the object, but setattr returns the error ('attribute-less object'). Is this due to the security limitations of Zope's own implementation of setitem and setattr? Any description of these limitations available somewhere? I suppose I can always try to find out from the appropriate .py file, but given my inexperience with Python, I don't have the time for that right now. If the issue is security, then is the only way to "fix up" (e.g. reformat a date string) items in a form record or records to do it in an external method? Cheers, Jean