In 1.4.1 this wasn't a problem:

struct TnhsAlarmOperations {
....
};

void dispatchTnhsImplicitAlarmOperations(in TnhsAlarmOperations operations);

In 2.0 it became a problem.  I had to change it to 

struct TnhsAlarmOperation {
...
};

void dispatchTnhsImplicitAlarmOperations(in TnhsAlarmOperation operations)

*** When I took the same original idl code and put into a much smaller
idl with ONLY TnhsAlarmOperations defined, the problem went away.

As far as I know, TnhsAlarmOperations is not a java keyword.  I will however
place the debugging information in lexer.java to get more info.

Most recently, we had the problem appear again by using a struct PONPackage.
Again, we tried it using it in a smaller idl, and the problem went away.
So, "Package" is within "PONPackage", but problem went away in a smaller idl.

Thanks for your help.  I'll help debug it with lexer.java