diff -up perl-5.10.0/regcomp.c.34507 perl-5.10.0/regcomp.c
--- perl-5.10.0/regcomp.c.34507	2009-03-09 08:44:12.000000000 -0400
+++ perl-5.10.0/regcomp.c	2009-03-09 08:45:36.000000000 -0400
@@ -8239,6 +8239,9 @@ parseit:
         *STRING(ret)= (char)value;
         STR_LEN(ret)= 1;
         RExC_emit += STR_SZ(1);
+        if (listsv) {
+            SvREFCNT_dec(listsv);
+        }
         return ret;
     }
     /* optimize case-insensitive simple patterns (e.g. /[a-z]/i) */