SB-EXT:ADD-PACKAGE-LOCAL-NICKNAME signals uninformative error when package is not found

[Jan Moringen]

What I do:
(sb-ext:add-package-local-nickname "nsp" "no-such-package")

What happens:
debugger invoked on a SB-KERNEL:SIMPLE-PACKAGE-ERROR in thread
#<THREAD "main thread" RUNNING {ABC0BA1}>:
  The name NIL does not designate any package.

What I expected:
debugger invoked on a SB-KERNEL:SIMPLE-PACKAGE-ERROR in thread
#<THREAD "main thread" RUNNING {ABC0B31}>:
  The name "no-such-package" does not designate any package.

The latter error is produced, for example, by:
(use-package "no-such-package")

$ sbcl --version
SBCL 1.1.5

$ uname -a
Linux ferberit 3.5.0-25-generic #38-Ubuntu SMP Mon Feb 18 23:28:26 UTC 2013 i686 i686 i686 GNU/Linux

(:ALIEN-CALLBACKS :ANSI-CL :C-STACK-IS-CONTROL-STACK :COMMON-LISP
 :COMPARE-AND-SWAP-VOPS :CYCLE-COUNTER :ELF :GENCGC :IEEE-FLOATING-POINT
 :INLINE-CONSTANTS :LARGEFILE :LINKAGE-TABLE :LINUX :LITTLE-ENDIAN
 :MEMORY-BARRIER-VOPS :MULTIPLY-HIGH-VOPS :OS-PROVIDES-BLKSIZE-T
 :OS-PROVIDES-DLADDR :OS-PROVIDES-DLOPEN :OS-PROVIDES-GETPROTOBY-R
 :OS-PROVIDES-POLL :OS-PROVIDES-PUTWC :OS-PROVIDES-SUSECONDS-T
 :PACKAGE-LOCAL-NICKNAMES :RAW-INSTANCE-INIT-VOPS :SB-CORE-COMPRESSION :SB-DOC
 :SB-EVAL :SB-FUTEX :SB-LDB :SB-PACKAGE-LOCKS :SB-SAFEPOINT
 :SB-SOURCE-LOCATIONS :SB-TEST :SB-THREAD :SB-UNICODE :SBCL
 :STACK-ALLOCATABLE-CLOSURES :STACK-ALLOCATABLE-FIXED-OBJECTS
 :STACK-ALLOCATABLE-LISTS :STACK-ALLOCATABLE-VECTORS
 :STACK-GROWS-DOWNWARD-NOT-UPWARD :UNIX :UNWIND-TO-FRAME-AND-CALL-VOP :X86)

[Stas Boukarev (stassats)]

commit 805689ba3c0ee4e42dbeef9b7bfd320e236813ca
Author: Stas Boukarev <email address hidden>
Date: Thu Mar 14 12:11:13 2013 +0400

    Better errors for package operations.

    Add some missing errors, make other errors to be of type
    sb-kernel:simple-package-error.

    Fixes lp#1154776.

    DELETE-PACKAGE should be signalling a continuable error, but wasn't
    since 1.0.37.44.