- added User-Agent
- value of x tag is a unix timestamp, not value in secs
- no more oversigning of recipient header, due to new ischedule-relaxed header canon
plus method to check ischedule is available for a domain/email and method to send a freebusy request
- ischedule-relaxed header cannonisation
- error xml response
- modified capabilities with serial and iSchedule-Capabilities header in every response
- using urls with mailto: schema for Originator and Recipient headers