CS4 - Java: ParagraphStyle.setAppliedLanguage() problem

Hello everybody!

I'm having trouble with setting  the applied Language for a ParagraphStyle.
Trying the way pointed out in the  Java CS4 Guide doesn't seem to work.
I have the following lines

<snip>

     LanguageWithVendors hyphenation_lwv = myApp.getIdentifiedChildLanguageWithVendors(Integer.parseInt(hyphenationLanguag e));

     ...

     //code

     ...

     ps.setAppliedLanguage(VariableTypeUtils.createObject(hyphenation_lwv));

</snip>

the latter throws the Exception #516, with the message " Ungültige Anforderung für Stammformat."

which roughly translates to "bad request for master/root format" (I'm sorry, I wasn't able to find the english version of the message)

Could someone please explain why it doesn't work?

Thanks in advance,

Arsenij