"Ada as a second language" question

[Darren New <dnew@san.rr.com>]

If you have this book and a few minutes, can you turn to page 879?

Therein you find a Load_Manager. The said Load_Manager demonstrates the
proper way to requeue an entry.

Unfortunately, it looks like if someone calls Set_Load while nothing
else is queued, and in particular while there's nothing queued on
Wait_To_Retry, then the whole system will block. Nothing's queued on the
private entry that opens the only public entry.

Am I missing something? Or is this an error in that code? Particularly
since a paragraph or two later the author says "As the example
illustrates, the 'Count attribute can be used in a barrier", except he
doesn't. 

TIA!

-- 
Darren New 
San Diego, CA, USA (PST). Cryptokeys on demand.
                   Who is this Dr. Ibid anyway, 
                  and how does he know so much?