I'm don't know how JessTab actually instantiates Jess but if it
creates a Main object and calls the main method then I believe you could
(assuming you have access to the Jess source code) modify the Jess
Main class (Main.java) as follows:
1. add the line
import nrc.fuzzy.jess.*;
2.
One last kick at this question ...
Perhaps you could convince the JessTab authors to include the option to
use the FuzzyRete object in JessTab. By default it could use the Jess
Rete object but with the presence of a command line switch or a configuration
setting it would use the FuzzyRete object.