redirect not working with IE

[eluser]tommebasso[/eluser]
after some days, in which i couldn't apply myself to the ie-problem, i now made up a test-function as sl3dg3hamm3r suggested, and this works fine with ie. ok then, it's my code that's tricking me out. but where?
i have no caching enabled, no compression and no echos (except ofcourse in the views), so there shouldn't be any data sent to the browser prior the redirection header. how can it be then, that i run into the trap only with ie?