SOAP trouble

Hi! I'm developing a moderately sized SOAP server application with PEAR SOAP (e.g. lots of already existing code), and have just replaced 0.8rc3 version of it with 0.8.1. Something's wrong - it looks like there's an infinite loop or recursion somewhere in SOAP/Base.php around line 584. The problem manifests itself by going out of memory (PHP's critical error 'allowed memory exhausted') serving a very simple request (method accepts two strings and returns a boolean). It seems like it fails even before executing my method implementation. I define lots of SOAP types (__typedef structure) for WSDL so it could be somewhere in there - problem is, I don't know how to begin to debug such a thing... Was something important changed between the two versions?