Version History
  ===============

  v.2.17 ( official, Mar 1998 )
  ------

  v.2.16 ( internal, Feb 1998 )
  ------
  o verifyta:
	New/improved hash function.
	Other improvements.

  v.2.15 ( internal, Jan 1998 )
  ------
  o verifyta:
        Temporary solution for problems with local optimisation.
 	-T problem solved.

  v.2.14 ( internal, Nov 1997 )
  ------
  o uppaal:
	Support for simta.text added.
	Support for simta.text removed.
	Filter setting removed (obsolete).	
  o xuppaal:
	[<--] problem fixed. Help menu is now activated with Ctrl-E.
	Zombie processes problem solved.
  o verifyta:
	GTA support added.
	General expressions on integer expressions added.
	Max and Min time derivation inactivated.

  v.2.13 ( internal, Oct 1997 )
  ------
  o simta.text: 
	Borned. Simulator with textual interface.
  o verifyta:
	Now handles integer guards on transitions with urgent actions in 
	a well defined way.
	Termination using max time constant.
	Max and Min time derivation added.
	Parametric leadsto algorithm added.

  v.2.12 (internal, Jul 1997)
  ------
  o verifyta:
	DBM optimisations (reduced number of close operations performed).
	Trace display problem fixed.
	Problems with parsing constants fixed.
	Live-lock warning added, displayed if a reachable state is found with
  	no outgoing transitions but the state allows for unbounded delay.
	

  v.2.11 (internal, Jun 1997)
  ----------------------------
  o verifyta:
	Integer implementation (v.2.09) refined.
	Constant declarations can now be mixed with other variable 
	declarations.

  v.2.10 (internal, Jun 1997)
  ---------------------------
  o xuppaal:
	Options->Deadlock Warnings added: turns on/off deadlock warning.
	Problem with interface to Local Reduction fixed.
  o Man pages: verifyta.1, uppaal.1, ta.5 updated.

  v.2.09 (internal, Jun 1997)
  ---------------------------
  o verifyta & checkta: 
	Added integer variables with explicit ranges. Declaration syntax
	changed. Also, new more general expressions added to integer
	variables. 

  v.2.08 (internal, May 1997)
  ---------------------------
  o verifyta:
	The waitlist now uses STL-lists again.
	The algorithm of adding states to the wait list has been changed 
	in a way that might alter the order in which the state space is 
	searched.
	Memory leaks removed.

  v.2.07 (internal, May 1997)
  ---------------------------
  o verifyta: 
	Memory leaks removed.

  v.2.06 (internal, May 1997)
  ---------------------------
  o verifyta:
	A lot of internal things changed, nothing visible to the user, 
	including: reimplementation of passedlist, and adding of some
	destructors.

  v.2.05 (internal, May 1997)
  ---------------------------
  o verifyta:
	Interval removed from implementation of integer variables.

  v.2.04 (internal, May 1997)
  ---------------------------
  o verifyta:
   	-h added. If given, verifyta print a short help message describing
	all the command line options.

  v.2.03 (internal, Apr 1997)
  ---------------------------
  o verifyta:
	-D added. If not given, a deadlock waring is displayed if a reached
        state have no possible outgoing transitions.

  v.2.02 (official, Mar 7 1997)
  -----------------------------
  o xuppaal:
	Help->Problems added,
	Run->Show Model and Run->Show Req. Spec improved, erroneous line
		breaks removed,
	Help text improved,
	Double click on verification output changes view point in property
		editor (if displayed).
  o Man pages: xuppaal.1 new, uppaal.1 updated.

  v.2.02 (beta, Mar 3 1997)	
  -------------------------
  o verifyta: 
	bug fix,
	number referring to lines in the property file now shown in 
		verification output.

  v.2.01 (beta, Feb 26 1997)
  --------------------------
  o uppaal is now a bash-script again, all verification options supported.
  o Comments and line breaks in formula format. 
	"//" - rest of line is ignored,
	"\" - line break in formula.
  o atg2ta, hs2ta, checkta, verifyta and uppaal compiled for MS-DOS
	(DPMI server required).
  o Man pages: uppaal.1 updated.

  v.2.00 (beta, Jan 16 1997)
  --------------------------
  o New optimisations in verifyta: -S for control structure reduction 
	(semantics changed from previous version), -C for disabeling use of 
	compact data structes for constraints (default enabled).
  o Man pages: verifyta.1 updated.
  o Support for new optimisations in xuppaal.

  v.1.99, (official, Dec 2 1996)
  ------------------------------
  o New optimisations in verifyta: -S for Control Structure Reduction, -T
	for reusing generated state space when checking several properties
	in sequence.
  o Support for new optimisations in xuppaal.
  o Simple Requirement Specification Editor added to xuppaal.
  o atg2ta, hs2ta, checkta, verifyta, uppaal and xuppaal compiled for Linux.