diff --git a/src/main/grammar/Grammar.flex b/src/main/grammar/Grammar.flex
index 43ff67a073b74d98a95e1c5b589851d320f1e483..cd7b52116e902a37816c8025be782de2aacdbb44 100644
--- a/src/main/grammar/Grammar.flex
+++ b/src/main/grammar/Grammar.flex
@@ -18,7 +18,7 @@ import com.intellij.psi.TokenType;
 
 
 WhiteSpace        = [ ] | \t | \f | \n | \r | \r\n
-ID                = [a-zA-Z$_][a-zA-Z0-9$_]*
+ID                = [:jletter:] [:jletterdigit:]*
 MultiLineComment  = [/][*][^*]+[*]+([^*/][^*]*[*]+)*[/]
 DocComment        = [/][*][*][^*]*[*]+([^*/][^*]*[*]+)*[/]
 SingleLineComment = [/][/] [^\n\r]* (\n | \r | \r\n)