Condition signalled initiating self seed

Created by: K1D77A

CL-USER> (ql:quickload :cl-isaac)
To load "cl-isaac":
  Load 1 ASDF system:
    cl-isaac
; Loading "cl-isaac"

(:CL-ISAAC)
CL-USER> (in-package :cl-isaac)
#<PACKAGE "CL-ISAAC">
ISAAC> (init-self-seed :is64 t)
; Debugger entered on #<SB-INT:INVALID-ARRAY-INDEX-ERROR expected-type: (INTEGER 0 (256)) datum: 41981>
[1] ISAAC> 

backtrace

Invalid index 41981 for (SIMPLE-ARRAY (UNSIGNED-BYTE 64) (256)), should be a non-negative integer below 256.
   [Condition of type SB-INT:INVALID-ARRAY-INDEX-ERROR]

Restarts:
 0: [RETRY] Retry SLY mREPL evaluation request.
 1: [*ABORT] Return to SLY's top level.
 2: [ABORT] abort thread (#<THREAD "sly-channel-1-mrepl-remote-1" RUNNING {100AC962B3}>)

Backtrace:
 0: (GENERATE-NEXT-ISAAC64-BLOCK #S(ISAAC64-CTX :RANDCNT 0 :RANDRSL #(935419330317120844 4361720847713160289 17134508137843955544 12276450597814484492 5733056363873583757 11868796555515008904 ...) :RANDME..
 1: (SCRAMBLE64 #S(ISAAC64-CTX :RANDCNT 0 :RANDRSL #(935419330317120844 4361720847713160289 17134508137843955544 12276450597814484492 5733056363873583757 11868796555515008904 ...) :RANDMEM #(4879904256235..
 2: (INIT-KERNEL-SEED :IS64 T)
 3: (INIT-SELF-SEED :COUNT 1 :IS64 T)
 4: (SB-INT:SIMPLE-EVAL-IN-LEXENV (INIT-SELF-SEED :IS64 T) #<NULL-LEXENV>)
 5: (EVAL (INIT-SELF-SEED :IS64 T))
 6: ((LAMBDA NIL :IN SLYNK-MREPL::MREPL-EVAL-1))
 --more--

This is sbcl 2.2.0 on Linux