[Zope] finding the owner of an object

[Steven Turoff]

Greetings,

I need to find out if a user owns a particular object. More specifically, I 
would like to present some HTML if the user is the owner of the current 
page. Something like:

<dtml-call "REQUEST.set('userName',_.SecurityGetUser().getUserName())">
<dtml-with owner_info mapping>
	<dtml-if "userName == id">
		Write some html
	</dtml-if>
</dtml-with>

This works fine if the user is a manager, however if not, I get:

Site Error

             An error was encountered while publishing this resource.

             Unauthorized

             You are not authorized to access owner_info.

Is there a security setting that I need to change? Or is there a better way 
of doing this?

Thanks,

Steve