Hi Alexander, like I already told Ralph, I did some messy hack with overwriting Zend_Search_Lucene::find() method. But I know that it was not the reason for this issue.
I copied the Zend/Search/ files again to the server and now the problem is gone. I have no idea how it happened that old files where copied to the server since I created a fresh new directory at the server and copied the 1.9.0 library to it. Hmm, maybe I should upload the library again to make sure that no other outdated files have been copied to my 1.9.0 branch. Anyway thanks for your comment, it really helped to find the solution! :-) Thanks and best regards, Ralf
