Sorry, I was a bit impatient and posted the same question in a newsgroup a few days before. There is an answer now: http://groups.google.de/group/comp.databases.postgresql/browse_thread/thread/36e5c65dd15b0388/1e5ff9b7e2c6863e?hl=de#1e5ff9b7e2c6863e Of course, if anyone has an additional idea, i'd appreciate it. Best regards, Ralf. -- Ralf Wiebicke Software Engineer exedio GmbH Am Fiebig 14 01561 Thiendorf Deutschland Telefon +49 (35248) 80-118 Fax +49 (35248) 80-199 ralf.wiebicke@xxxxxxxxxx www.exedio.com