When using the old -DPOCO_STATIC=ON to configure CMake for static libraries, the message:

 message(WARNING "POCO_STATIC has been deprecated. Please use BUILD_SHARED_LIBS instead.")

could be mis-interpreted to mean POCO does not support static builds at all.
Better change the message to:

POCO_STATIC has been deprecated. Please use BUILD_SHARED_LIBS=NO to build static libraries.