Explanation error - FaCT++ Kernel: unsupported operation 'tellDatatypeDeclaration'

What steps will reproduce the problem?
1.Add an individual with the a datatype property asserion (for example 
assigning an integer value like in the attached example owl file)
2. Creating query in Protégé DL-Query Tab to fetch the above individual
3. While clicking explanation button following error occurs: 
"ReasonerInternalException: FaCT++ Kernel: unsupported operation 
'tellDatatypeDeclaration'". 

What is the expected output? What do you see instead?
An error is logged instead of displaying the expected explanation - see 
attached stack trace. 
The error does not occur while using the explanation button in the other 
Protégé tabs. 
This error can not be reproduced with other reasoners (Pellet, Hermit). 
I've experienced this Fact++ behavior also outside Protégé while using OWLAPI 
DefaultExplanationGenerator on a similar OWL file.

What version of the product are you using? On what operating system?
1) Protégé 4.2.0 & 4.1.0(build 249, 239), Factplusplus Plug-in 1.5.2 & 1.5.3
2) custom JAVA aplication build on owlapi-3.2.4

Please provide any additional information below.

Original issue reported on code.google.com by piotrnowara@gmail.com on 9 Feb 2012 at 7:25

Attachments:

dgu123 / factplusplus

Explanation error - FaCT++ Kernel: unsupported operation 'tellDatatypeDeclaration' #46