Can't get hashes to work

So, I have been working on converting everything over to use  
BeansWrapper, but now I can't seem to get my hashes to work at all,  
even with DefaultObjectWrapper. I'm assuming this is something simple,  
but I can't figure it out. Here is my simple bean:

public class Bean {
     public Map<Integer, String> coolMap = new HashMap<Integer,  
String>();
     private int age;

     public int getAge() {
         return age;
     }

     public void setAge(int age) {
         this.age = age;
     }
}


Here's the code that I'm using to execute the template:

         BeansWrapper ow = new BeansWrapper();
         ow.setExposeFields(true);
         ow.setSimpleMapWrapper(true);

         Bean bean = new Bean();
         bean.coolMap.put(1, "test");
         bean.setAge(42);

         Map<String, Object> context = new HashMap<String, Object>();
         context.put("bean", bean);

         Template template =  
freeMarkerConfiguration.getTemplate(templateName, locale);
         template.setObjectWrapper(ow);
         template.process(root, writer);


The template is pretty simple:

     [#ftl/]
     Bean [#list bean.coolMap?keys as key]${key} ${bean.coolMap[key]}  
[/#list] ${bean.age}


The error I'm getting is just the standard "Expected number, sequence,  
or string. bean.coolMap evaluated instead to  
freemarker.ext.beans.SimpleMapModel". It is failing at the $ 
{bean.coolMap[key]} statement. However, that should work fine, right?

-bp



------------------------------------------------------------------------------
Crystal Reports - New Free Runtime and 30 Day Trial
Check out the new simplified licensing option that enables unlimited
royalty-free distribution of the report engine for externally facing 
server and web deployment.
http://p.sf.net/sfu/businessobjects