[imp] strange language problem rh7.3

[fabian-imp@spline.de]

Hello everybody,

i\'ve some strange problems with language settings
after \"migration\" from 3.1rc3->3.1final.

All German-Internetexplorers i tried(6 & 5.5) ignore any language setting i choose or try to set explicitly.
My default language in horde is de_DE.
An english version of Mozilla is using the correct
language after login (the language of the login is
not changing, although the page is reloaded on
dropdown-change).
Another Mozilla(en) I tried is switching languages between the choosen one and english irregulary on
new page loads while using imp.

Any Ideas?
Thanks
Fabian Ruff