This may very well have been true back in 2001, I do remember having problems if I loaded DBI before fork()ing, but I AM running several multithreaded services (daemons for the Unixers) for two or three years already. Works fine. I do not keep creating and destroying threads though, in one service I only have two threads ("watcher" and "worker"), the number of threads in the other depends on the INI file, but again I create them upfront.