Push kernel/user limit to 2GiB, so Mach can address up to close to 2GiB memory.
This makes glibc's local-bigmem.diff patch mandatory.

diff --git a/i386/include/mach/i386/vm_param.h b/i386/include/mach/i386/vm_param.h
index 6d7c5f3..839ae68 100644
--- a/i386/include/mach/i386/vm_param.h
+++ b/i386/include/mach/i386/vm_param.h
@@ -73,6 +73,6 @@
    with that.
    */
 #define VM_MIN_ADDRESS		(0)
-#define VM_MAX_ADDRESS		(0xc0000000UL)
+#define VM_MAX_ADDRESS		(0x80000000UL)
 
 #endif	/* _MACH_I386_VM_PARAM_H_ */