Escaping a utf-8 string

I am sure this is a commonly asked question, but I couldn't find it in the
FAQ: I want to escape an xsl string.

Unfortunately I need the ascii value of the characters in it. I understand
however, that since things are unicode it is not this simple. Fortunately, I
actually want the string as utf-8 and to pop off a character at a time from
the utf-8 string. This way I can write a nice email subject line:

A contrived example:
	=?utf-8?Q?bleh bleh =FD=AC blah blah?=

Where presumably =FD=AC is some valid utf-8 encoding sequence

Also, I would like to be able to encode uris. I know that xfunctions provide
a uri-escape() function, but this is not on my target xsl platforms (IE6 xsl
and libxslt1). Incidently, if this worked I could just
translate(uri-escape(str, true), '%', '=') for the email example and use
uri-escape for the uris I need to deal with.

Again, all would be simple if only I could extract a hexademincal encoding
of the utf-8 string in some way. Getting the ascii numeric value would work,
or in fact, a function like "hexify" or something that takes the string and
just output AB87B3AF873E or something would be fine since I could then stick
=s and %s in the stream appropriately.

Does anyone know of a way to get past this barrier in xsl?

Thanks; this is really important to me.

-- 
Wesley W. Terpstra <wesley@xxxxxxxxxxx>

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