UTF-8 to ASCII

I have a doubt about the function to_ascii() and what the documentation
says.

Basically, I passed my DB from latin1 to UTF-8, and I started getting an
error when using the to_ascii() function on a field of one of my DB [1]:

ERROR:  la conversión de codificación de UTF8 a ASCII no está soportada

OK, it's in spanish, but basically it says that the conversion UTF8 to
ASCII is not supported, but in the documentation [2] I see this in the
"Table 9-7. Built-in Conversions":

utf8_to_ascii    UTF8    SQL_ASCII

Is the documentation wrong or something?

I'm on postgresql-8.1.8, and as you can see, I'm checking the
corresponding documentation.

[1]: This I already solved using convert() to pass from UTF to Latin1,
and after that I do a to_ascii().
[2]:
http://www.postgresql.org/docs/8.1/interactive/functions-string.html#FTN.AEN7625

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