controls what happens when a CLtL1-style
form which attempts to create a package is processed. This refers to the specification in Common Lisp the Language, first Edition, which preceded ANSI Common Lisp and specified
as a function with keyword arguments.
Handle according to the value of *handle-old-in-package*.
Signal a warning and create the package.
Signal a continuable error.
LispWorks User Guide and Reference Manual - 21 Dec 2011