[antlr-interest] Antlr3b6 [bug?] Can't find template matchSetTrack.st

[femto gary]

for the following grammar, antlr reports error:
ANTLR Parser Generator  Version 3.0b6 (Jan 31, 2007)  1989-2007
warning(200): Rubyv3.g:101:32: Decision can match input such as "SEMI" using mul
tiple alternatives: 1, 2
As a result, alternative(s) 2 were disabled for that input
error(10):  internal error: Rubyv3.g : java.lang.IllegalArgumentException: Can't
 find template matchSetTrack.st
org.antlr.stringtemplate.StringTemplateGroup.lookupTemplate(StringTemplateGroup.
java:485)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:372)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:384)
org.antlr.stringtemplate.StringTemplateGroup.lookupTemplate(StringTemplateGroup.
java:464)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:372)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:384)
org.antlr.stringtemplate.StringTemplateGroup.lookupTemplate(StringTemplateGroup.
java:464)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:372)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:384)
org.antlr.stringtemplate.StringTemplateGroup.lookupTemplate(StringTemplateGroup.
java:464)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:372)
org.antlr.stringtemplate.StringTemplateGroup.getInstanceOf(StringTemplateGroup.j
ava:384)
org.antlr.codegen.CodeGenTreeWalker.getTokenElementST(CodeGenTreeWalker.java:160
)
org.antlr.codegen.CodeGenTreeWalker.set(CodeGenTreeWalker.java:2557)
org.antlr.codegen.CodeGenTreeWalker.atom(CodeGenTreeWalker.java:2243)
org.antlr.codegen.CodeGenTreeWalker.element(CodeGenTreeWalker.java:1370)
org.antlr.codegen.CodeGenTreeWalker.alternative(CodeGenTreeWalker.java:1115)
org.antlr.codegen.CodeGenTreeWalker.block(CodeGenTreeWalker.java:999)
org.antlr.codegen.CodeGenTreeWalker.rule(CodeGenTreeWalker.java:725)
org.antlr.codegen.CodeGenTreeWalker.rules(CodeGenTreeWalker.java:516)
org.antlr.codegen.CodeGenTreeWalker.grammarSpec(CodeGenTreeWalker.java:458)
org.antlr.codegen.CodeGenTreeWalker.grammar(CodeGenTreeWalker.java:305)
org.antlr.codegen.CodeGenerator.genRecognizer(CodeGenerator.java:415)
org.antlr.Tool.processGrammar(Tool.java:329)
org.antlr.Tool.process(Tool.java:266)
org.antlr.Tool.main(Tool.java:69)

doing a google search reveals somebody has also this problem:
http://www.antlr.org/pipermail/antlr-interest/2007-January/019038.html,
is this an antlr3b6 bug?

grammar Rubyv3;

options {
        output=AST;
}
tokens {
	// 'imaginary' tokens
	STATEMENT_LIST;
	STATEMENT;
	IF;
	RPAREN_IN_METHOD_DEFINATION;
	BODY;
	CALL;
	ARG;
	//COMPSTMT;
	SYMBOL;
	BLOCK;
	MULTIPLE_ASSIGN;
	MULTIPLE_ASSIGN_WITH_EXTRA_COMMA;
	BLOCK_ARG;
	BLOCK_ARG_WITH_EXTRA_COMMA;
	MRHS;
	NESTED_LHS;
	SINGLETON_METHOD;
	STRING;
}

/*@rulecatch {
catch (RecognitionException e) {
throw e;
}
}*/

@header {
package com.xruby.compiler.parser;
}
@lexer::header {
package com.xruby.compiler.parser;
}

@members{
	private int can_be_command_ = 0;

	protected void enterScope()	{assert(false);}
	protected void enterBlockScope()	{assert(false);}
	protected void leaveScope()	{assert(false);}
	protected void addVariable(Token id)	{assert(false);}
	protected void setIsInNestedMultipleAssign(boolean v)	{assert(false);}
	protected void
tellLexerWeHaveFinishedParsingMethodparameters()	{assert(false);}
	protected void tellLexerWeHaveFinishedParsingSymbol()	{assert(false);}
	protected void
tellLexerWeHaveFinishedParsingStringExpressionSubstituation()	{assert(false);}
	protected void
tellLexerWeHaveFinishedParsingRegexExpressionSubstituation()	{assert(false);}
	protected void
tellLexerWeHaveFinishedParsingHeredocExpressionSubstituation()	{assert(false);}

	
}

@lexer::members
{
	//The following methods are to be implemented in the subclass.
	//In fact they should be 'abstract', but antlr refuses to generate
	//abstract class. We can either insert 'abstract' keyword manually
	//after the lexer is generated, or simply use assert() to prevent
	//these function to run (so you have to overide them). I choosed
	//the later approach.
	protected boolean expectOperator(int k) throws
Exception		{assert(false);return false;}
	protected boolean expectUnary()	 throws
Exception			{assert(false);return false;}
	protected boolean expectHash()					{assert(false);return false;}
	protected boolean expectHeredoc()				{assert(false);return false;}
	protected boolean expectLeadingColon2()		{assert(false);return false;}
	protected boolean expectArrayAccess()				{assert(false);return false;}
	protected boolean lastTokenIsDotOrColon2()		{assert(false);return false;}
	protected boolean lastTokenIsSemi()				{assert(false);return false;}
	protected boolean
lastTokenIsKeywordDefOrColonWithNoFollowingSpace()			{assert(false);return
false;}
	protected boolean
lastTokenIsColonWithNoFollowingSpace()			{assert(false);return false;}
	protected boolean shouldIgnoreLinebreak()			{assert(false);return false;}
	protected int trackDelimiterCount(char next_char, char delimeter, int
delimeter_count)	{assert(false);return 0;}
	protected boolean isDelimiter(String next_line, String
delimiter)	{assert(false);return false;}
	protected boolean isAsciiValueTerminator(char
value)	{assert(false);return false;}
	protected boolean justSeenWhitespace()	{assert(false);return false;}
	protected void setSeenWhitespace()			{assert(false);}
	protected boolean expressionSubstitutionIsNext()	throws
Exception	{assert(false);return false;}
	protected boolean spaceIsNext()	throws Exception	{assert(false);return false;}
	protected void setCurrentSpecialStringDelimiter(char delimiter, int
delimiter_count)	{assert(false);}
	protected void updateCurrentSpecialStringDelimiterCount(int
delimiter_count)	{assert(false);}
}

program
		:	statement_list
		;

statement_list
		:	statement* -> ^(STATEMENT_LIST statement*)
			;

/*terminal
		:	SEMI!
		|	LINE_BREAK!
		;*/
statement
	:	expression (modifier_line)* SEMI? -> ^(STATEMENT expression
(modifier_line)*)
	|       SEMI!
	;

modifier_line
	:(IF_MODIFIER|UNLESS_MODIFIER|WHILE_MODIFIER|UNTIL_MODIFIER|RESCUE_MODIFIER)^
expression
		;
IF_MODIFIER     :  'if';
UNLESS_MODIFIER :  'unless';
WHILE_MODIFIER  :  'while';
UNTIL_MODIFIER  :  'until';
RESCUE_MODIFIER :  'resuce';

SEMI	:';'
	;

LINE_BREAK
	:'\r'? '\n'{skip();}
	;
//OMIT_LINE_BREAK
//	:	LINE_BREAK* {skip();}
//	;
//emptyable_expression
//	:	expression|;
expression
	:	'expression0' | 'expression1' | 'expression2'|boolean_expression|
block_expression|if_expression|unless_expression;
	
block_expression
	:	'begin' body 'end';
body	:	statement_list;
boolean_expression
	:	'false'|'nil'|'true';
if_expression
	:	'if' b=boolean_expression ('then'|':'|LINE_BREAK)
	        body0=body ('elsif' b1=boolean_expression
('then'|':'|LINE_BREAK) body1+=body)*
	        ('else' body2=body)?
	        'end' -> ^(IF $b $body0 $b1* $body1* $body2? )
	        ;
unless_expression
	:	'unless' boolean_expression ('then'|':'|LINE_BREAK)
	        body
	        ('else' body)?
	        'end';	
	
WS	:	(' ' | '\t') { skip(); }
	;
ID	:	('a'..'z' | 'A'..'Z') (('a'..'z' | 'A'..'Z') | ('0'..'9'))*
	;