Index: org/python/core/PyInteger.java
===================================================================
RCS file: /cvsroot/jython/jython/org/python/core/PyInteger.java,v
retrieving revision 2.18
diff -c -r2.18 PyInteger.java
*** org/python/core/PyInteger.java	5 Nov 2002 17:04:17 -0000	2.18
--- org/python/core/PyInteger.java	20 Dec 2002 19:00:19 -0000
***************
*** 339,344 ****
--- 339,346 ----
  
          if (rightv > 31)
              return new PyInteger(0);
+         else if(rightv < 0)
+             throw Py.ValueError("negative shift count");
          return Py.newInteger(value << rightv);
      }
  
***************
*** 348,353 ****
--- 350,358 ----
               rightv = ((PyInteger)right).value;
          else
               return null;
+ 
+         if(rightv < 0)
+             throw Py.ValueError("negative shift count");
  
          return Py.newInteger(value >> rightv);
      }