[antlr-interest] Attribute in Tree grammar. Semantic predicates with Alternative clause Problem

[Петров Александр]

Hello,

I'm using semantic predicates in tree grammar:

//deviceID is a rule
deviceFuncID
:     ^(NODE1 ^(NODE2 ^(NODE3 deviceID)))
        (
	{
                   //IsID function has signature:  bool IsID(string id)
                    IsID(
	           $deviceID.text,
                          )
                  }?
	-> oneTemplate(...)
                |-> otherTemplate(...)
         );

deviceID	:	'this'->{%{"this"}}

But when I try to compile generated C# code (antlr 3.1.1)I have many
errors like that:

---- The name 'deviceID25' does not exist in the current context

In antlr 3.0.1 such grammar produce compilable code.
If I rewrite that code as (remove brackets)

deviceFuncID
:     ^(CCALL ^(CSYNCCALL ^(OBJECTNAME deviceID)))

	{
                    IsID(
	           $deviceID.text,
                          )
                  }?
	-> oneTemplate(...)
               // |-> otherTemplate(...)

Then all right, but I want to have alternative clause for semantic predicate.
If I uncomment alternative clause, then I have:

---- error(201):  The following alternatives can never be matched: 2

What should I do ? What is the cause of such errors ?

Thank you