--- Compress-LZF/LZF.xs	2001/09/27 20:05:38	1.4
+++ Compress-LZF/LZF.xs	2001/09/27 20:08:05	1.5
@@ -267,6 +267,9 @@
         PROTOTYPE: $
         PPCODE:
 
+        if (!SvPOK (sv))
+          croak ("Compress::LZF::sthaw(): argument must be a string");
+
         if (IN_RANGE (SvPV_nolen (sv)[0], MAGIC_LO, MAGIC_HI))
           {
             switch (SvPVX (sv)[0])
@@ -298,7 +301,7 @@
 
                   SPAGAIN;
 
-                  XPUSHs (POPs); /* this is a nop, hope the compiler also knows this */
+                  /*XPUSHs (POPs); this is a nop, hopefully */
 
                   break;