In the last few days on and off I've been trying to locate a problem with a fairly complicated Perl daemon using POE which was taking a huge amount of time to return a large file via LWP::UserAgent. It's taken a while since in reality we were not doing a simple HTTP GET and the circumstances under which the problem occurs are difficult to set up. However, I've at last tracked it down to taint mode.
A great deal of issues arise in the dbi-users mailing list and to me personally concerning ODBC connection issues so I thought I'd describe the ODBC connection process here (with a slight Perl angle since I look after DBD::ODBC). The information here should be of general interest to anyone using ODBC.