malloc region (kmem_map) to be wrong and semi-random on systems with more
than 1GB of RAM. This is not a complete fix, but is sufficient for
machines with 4GB or less of memory. A complete fix will require some
changes to the getenv stuff so that 64bit values can be passed around.
NOT FIXED: machines with more than 4GB of RAM (e.g. some large Alphas)
since we're still using ints to hold some of the values.
Reviewed by: bde