IO::Socket::INET "isa" IO::Socket "isa" IO::Handle "isa" Exporter so if any of those have a AUTOLOAD, then IO::Socket::INET does. One of the many ugly pitfalls of using inheritance in Perl.

Another ugly thing is that the default AUTOLOAD that often gets used gives this silly error about not finding a *.al file when the real problem is that the module user has mistyped the method name. There is no blocking.al file because there is no "blocking" method for that module. That error message is hugely misleading and I go out of my way to avoid it in the modules I write.

blocking() is supposed to be an IO::Handle method. I suspect the problem is that this wasn't present in whatever version of Perl is being used. The problem could probably be solved by upgrading Perl.