Simple (?) question about ""

[Rich Wagner]

Hi,
I'm having trouble specifying a particular "available" task.  Here's 
what I want, though Ant isn't happy with it:

   <target name="check_for_zip_file">
       <available property="ZIP_FILE_EXISTS">
           <filepath>
               <include name="${DIR}/*.zip"/>
               <exclude name="${DIR}/not_this_one.zip"/>
           </filepath>
       </available>
   </target>
Ant says:  "The <path> type doesn't support the nested 'include' element."
OK, but can anyone tell me how to write what I want?  Essentially, set 
the ZIP_FILE_EXISTS property if there's at least one match to 
"${DIR}/*.zip", though NOT counting "${DIR}/not_this_one.zip"...

Thanks in advance,
Rich Wagner