--- IO-AIO/schmorp.h	2009/07/14 00:14:27	1.2
+++ IO-AIO/schmorp.h	2009/07/14 00:32:27	1.3
@@ -137,20 +137,20 @@
 {
   HV *st;
   GV *gvp;
-  CV *cv = sv_2cv (cb_sv, &st, &gvp, 0);
 
-  return (SV *)cv;
+  SvGETMAGIC (cb_sv);
+  return SvOK (cb_sv) ? sv_2cv (cb_sv, &st, &gvp, 0) : 0;
 }
 
 static SV *
 s_get_cv_croak (SV *cb_sv)
 {
-  cb_sv = s_get_cv (cb_sv);
+  SV *cv = s_get_cv (cb_sv);
 
-  if (!cb_sv)
+  if (!cv)
     croak ("%s: callback must be a CODE reference or another callable object", SvPV_nolen (cb_sv));
 
-  return cb_sv;
+  return cv;
 }
 
 /*****************************************************************************/