Next (in order of descending priority/precedence):
* Full standards compliance review for the engine and all fully implemented 
  sieve extensions. Issues discovered so far:
	- :matches : match values must only be changed when the test 
	  matches.
	- If an address is not syntactically valid, then it will not be matched
	  by tests specifying ":localpart" or ":domain".
	- Fix/Report issues listed in 'doc/rfc/RFC Controversy.txt'
* Code cleanup 
* Full security review. Enforce limits on number of created objects, script 
  size, execution time, etc...
	- Limit the string size
	- Limit the string list size
	- Limit the depth of the AST, i.e. command block and test list
	  nesting.
	- Limit the maximum number of included scripts
	- Make (configurable) limit on the number of redirects
	- Malicious/Broken binary can allocate large variable storage
* Finish the test suite for the base functionality
* Make sure cmusieve can be replaced seamlessly with the new plugin.

* ## MAKE A FIRST RELEASE ##

* Imapflags: merge execution of setflags, removeflags and addflags into one 
  common implementation. 
* Add normalize() method to comparators to normalize the string before matching
  (for efficiency).
* Verify outgoing mail addresses at runtime when necessary (e.g. after variables 
  substitution)
* Warn about the use of syntactically invalid header names. 
* Implement notify extension with sole support for mailto mechanism. 
* Implement dropping errors in the user's mailbox as a mail message.
* Provide a solution for mail_get_headers_utf8 reparsing the whole message each
  time it is called (header and address test; Timo might provide solution from
  within Dovecot)
* Build a sieve tool to filter an entire existing mailbox through a sieve script.
* Build a server with test mail accounts that processes lots and lots of mail 
  (e.g. spam, mailing lists etc.)
* Make this implementation conform section 2.7.2 of RFC3028 (Comparisons Across
  Character Sets). 
* Implement executing an arbitrary number of scripts sequentially, acting on the 
  same set of result actions.
* Implement comparator-i;unicode-casemap
* Implement environment extension
* Implement date and index extensions
* Optimize code containing true/false tests to omit explicit JMP opcodes
  (i.e. optimize the test away and any code that negatively depends on it)
* Automate script tests; i.e. build a test suite.

* Use lib/str-find.h for :contains and :matches match types  
* Add development documentation, i.e. comment on library functions and document
  the binary and byte-code format. 
* Make the engine and its extensions much more configurable. Possibly this can 
  be merged with Dovecot's new master config implementation.
* Implement editheader extension
* Implement mimeloop extension
* Give the byte code format some more thought, it is currently quite rough and
  to the point. 
* Try to implement proposed notify mechanisms other than mailto. Currently: xmpp
  and sip
* Implement namespace support for variables extension 
  (possibly needed by test suite; in that case priority is much higher)