[TYPO3] realurl not working when logged into BE

[media.res | alex widschwendter]

hi,

has somebody experienced the same problem as described in the subject?
if im not logged in the BE, realurl is working as expected, but as soon 
as i log in, the world famous error "Reason: Segment "bla bla" was not a 
keyword for a postVarSet as expected!"

any solutions or experiences out there?

tia alex