Known bugs
----------

. the CGAL N ln N methods cannot handle coincident points. Events with
  more than one particle having identical rapidity,phi values should be 
  clustered with an alternative strategy. If this poses a severe
  issue to someone, it will be fixed.

----------------------------------------------------------------------
Other issues to be aware of
---------------------------

. Some algorithms can have ambiguities in the clustering steps and we
  do not guarantee that different internal clustering strategies (or
  different fastjet versions) will always resolve the ambiguities
  identically. This issue doesn't arise with normal particle inputs.

  However:

  - Pythia sometimes produces massive particles with pt=0; phi is then
    ill-defined, while the rapidity is finite and we make no
    guarantees about how we treat it.

  - inputs that lie on a perfect grid in rapidity-phi (e.g. one
    interpretation of a calorimeter) cause many interparticle
    distances to be identical. In the kt, Cambridge/Aachen and anti-kt
    algorithms, many dij can therefore also be identical. The choice
    of which dij to take is then ambiguous and what fastjet actually
    does may depend on: the compiler, the machine architecture
    (because of rounding errors), the fastjet version.

    Physically this issue should not change the jets
    much. Nevertheless, one might choose to break any degeneracy
    explicity, e.g. using information from the location of energy
    deposits in each calorimeter tower, so that the inputs are not on
    a perfect grid.

----------------------------------------------------------------------
Probably solved
---------------

. Compilation issues have been reported under windows with the VC7.1
  compiler. We have incorporated fixes proposed by Ivan Belyaev for
  this, but do not have access to an appropriate machine to test it
  ourselves. (NB: it in any case works with cygwin).



