[css3-syntax] Parseable at-rules

This is merely a request for confirmation:

Considering the following at-rules:

(1)  @import {;}
(2)  @mysum (a+ (b-c;
(3)  @punctuationchars [.-,;:_?!];
(4)  @validchars [?*./(){a-z0-9}@_ ];

Am I correct in my interpretation of the spec [1] that only (3) will
generate a fatal parsing error (with (4) actually being parsed as two at-
rules)?

[1] <http://www.w3.org/TR/2003/WD-css3-syntax-20030813/#at-rules>

Regards, Christian.