Configuring Async::Callback No supported threading library found (mutex support disabled) Enter path to install Callback.h in: [] Will install Callback.h in /Callback.h WARNING: H takes a ARRAY reference not a string/number. Please inform the author. Checking if your kit is complete... Looks good Checking if your kit is complete... Looks good Writing Makefile for Async::Callback::Test Can't use string ("Callback.h") as an ARRAY ref while "strict refs" in use at /Users/cpanrun/build/5.10.0/lib/ExtUtils/MM_Unix.pm line 432.