How to suppress implicit conversions when spliiting up the query string into parameters

[KHZ (SAW)]

Hi world.
 
We’ve severe problems if a URL contains an umlaut. For URL usage we encode
strings using UTF-8, i.e. “ü” (which would be ü in HTML) can be viewed
as “%c3%bc”. Getting the request parameter I’ld expect the same string. But
we see 2 characters. Obviously it’s interpreted as ISO8859-1 and so we see
“ü”. It’s obviously p.i.t.ar. to convert such a thing directly to “ü”.
 
As a workaround we split the query string ourselves (Java) and store it in a
hash map. Using these data we can apply the decoding using UTF-8. There it
works good. But the application is big. So we want to remove the real
problem.
 
I assume that it’s some setting in some XML file. How can we suppress such
implicit conversions?
 
If my assumption is wrong that Tomcat splits up the query string then please
give me a hint which tool is responsible for that.
 
Best regards,    Karl-Heinz.