Re: [bug] name and id

Can you clarify for me - Why is the following true?
 
* "Karl Dubost" <karl@w3.org
<mailto:karl@w3.org?Subject=Re:%20%5bbug%5d%20name%20and%20id&In-Reply-T
o=%3c006901c0653e$406fcb60$c7e0a8c0@de%3e&References=%3c006901c0653e$406
fcb60$c7e0a8c0@de%3e> > wrote:
| ****
| ID and NAME tokens must begin with a letter ([A-Za-z]) and may be
| followed by any number of letters, digits ([0-9]), hyphens ("-"),
| underscores ("_"), colons (":"), and periods (".").
http://lists.w3.org/Archives/Public/www-validator/2000Dec/0018.html
 
 
What are the implications for accessibility when ID's begin with an
underscore say?
 
I look forward to hearing from you.
 
Kind regards,
 
Pete Comley
Virtual Surveys Limited
Tel: +44 1256 76 75 76
Email: pete.comley@virtualsurveys.com
Web: www.virtualsurveys.com
 
 
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