[Zope] Referring to objects with an integer as id?

[Peter Arvidsson]

How do I refer to an object that has an integer as id?

I have pdf-files stored in a folder called "pdf". Now I want to be able
to check their filesize. I looked in the API and found that this is done
with getSize(self). I have no problem to refer to objects that do not
have an integer as id. For example for the pdf-file with id "temppdf"
this works: <dtml-var "pdf.testpdf.getSize()">

I have tried a number of different syntaxes to be able to check the
filesize of an objct with an integer as id but nothing has worked
For the pdf-file with id "11111111" I have tried this:

<dtml-var "pdf.11111111.getSize()"> (gives me syntax error)
<dtml-var "pdf.[11111111].getSize()"> (gives me syntax error)
<dtml-var "pdf.['11111111'].getSize()"> (gives me syntax error)
<dtml-var "pdf._['11111111'].getSize()"> (says I am unauthorized but I
am sure I am not because I could access the same object if I gave it a
string as id instead of an integer. I am the owner of both the object
and folder and I have all privilages. Superuser wasnt authorized
either.)
<dtml-var "pdf._[11111111].getSize()"> (also says I am unauthorized)

I have also tried all those combinations with _len() but that doesnt
work either...

Could someone please tell me how I can get the filesize of my objects
with integers as their id?