[Zope] adding methods to AccessRule

Up until now, I have only used AccessRules for redirecting. I am adding additional logic to log info from the requests. I wrote a small DTML_Method to write info to a database and added it to the AccessRule <dtml-var smallscript>. However, everytime I try to save this line in the AccessRule, I get locked out of the folder and have to use "undo" to get back in. What am I doing that is offending AccessRules? TIA, Trevor