filtering depending on the value of a boolean field

Hi everybody,
 
 
I'd like to create a filter based on the value of a boolean field of my container.
first i have my declaration of my container, with my field:
 
<content:declareField name="toto" title="toto" titleKey="toto" bundleKey="<%= CompositePartenaire.BUNDLE_ID%>" type="Boolean" />

so i create a checkbox, to filter on the value of this field :
<input type="checkbox" name="<%=paramName%>" id="<%=paramName%>" value="true" <%=paramValue? "checked=\"checked\"" : "" %>/>

And after the submission i create the filter :

booleanFilter.addClause(ContainerFilterBean.COMP_EQUAL, String.valueOf(paramValue));

paramValue is the value sent by the checkbox.
 
But, it doesn't work !!  i guess that the value to compare is not "String.valueOf(paramValue)", but i don't know what must be my second parameter
 
Have someone already been dealing with such filters??? 
 
Thanks a lot !
Guillaume KUHMEL