In through php_info() where the WSDL cache is held (/tmp), but I don\'t necessarily know if it is safe to delete all files starting with WSDL.
php_info()
/tmp
Remove all wsdl* files in your /tmp folder on the server.
wsdl*
WSDL files are cached in your default location for all cache files defined in php.ini. Same location as your session files.