Referee 1 *******************************************

E: Referee Comments (For Author and Editor) 
------------------------------

  Good paper presenting not only Ecce but gives also some
general topics to mention for building PSEs.

  Some parts of the paper gives statements, that should be
provided with further information, for example, references
to other documents. In particular:
Section 3.3, paragraph 4: Why does RSL not provide the
necessary customization, what is missing?
Section 3.3, paragraph 9: What deficiencies do existing
protocols have, what are your requirements? 

  As the paper presents an very application-related PSE, I 
suggest to add a 'typical' screenshot of Ecce.

  Also the paper should say something about the availability
of the Ecce environment (Is it free? Can it be used by 
others? Can it be downloaded?)


Referee 2 *******************************************

E: Referee Comments (For Author and Editor)  ------------------------------

The paper presents an alternative to browser-based problem
solving environments and provides an interesting case study of redesigning
a "legacy" PSE to use web and grid technologies.  Overall, the paper
had a very strong discussion of data management and information services,
which deserve publication and dissemination to the grid computing environment
community.

I recommend the following addition/clarification to the paper:

o Security discussions are sprinkled throughout the paper.  The paper
would benefit from a single section describing Ecce's security
infrastructure and future services to be used, such as Akenti.

Referee 3 *******************************************

E: Referee Comments (For Author and Editor)  
The paper describes the design and implementation of a prototype system which provides high-
level middleware services that incorporate lightweight services that can be incorporated
into problem-solving environments, portals, etc. The paper is well organized and fits to the
overall theme of the special issue.