Spring / Grails - file upload fails with NULL object

I am having a helluva time with multipart upload in Grails. Most sources point to that being very simple, and no additional configuration required. Yet that approach was giving me a null object on uploaded file.

Here is the exception i get:
ERROR errors.GrailsExceptionResolver  - Cannot get property 'originalFilename' on null object
java.lang.NullPointerException: Cannot get property 'originalFilename' on null object

I fiddled with adding Spring configuration to the resources.groovy:
beans = {
      multipartResolver(org.springframework.web.multipart.commons.CommonsMultipartResolver){
            maxInMemorySize=10240
            maxUploadSize=10000000
            }
}

And attempted to do the same in the WEB-INF/applicationContext.xml:

   <bean id="multipartResolver"
            class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            <property name="maxUploadSize" value="5000000"/>
   </bean >

Here the .gsp form code:
<g:form action="rawUpload" method="POST" name="uploadImageForm" enctype="multipart/form-data">
    <tr><td colspan="2" align="right"><div id="showImg" align="center">&nbsp; </div></td>
    <td colspan="2" align="right">
          <input type="file" name="Image" />
         </td></tr>
    <tr><td colspan="4">
            <div class="button" align="right">&nbsp;
                   <button type="submit" id="ImageBtn" name="ImageBtn" value="Upload Image" >Upload Image</button>
            </div>
      </td></tr>
      </g:form>      

And in the controller:

//import org.springframework.web.multipart.MultipartHttpServletRequest;
//import org.springframework.web.multipart.commons.CommonsMultipartFile;

      def rawUpload = {
            //Spring MultipartHttpSevletRequest
            //MultipartHttpServletRequest mpr = (MultipartHttpServletRequest)request;
            //CommonsMultipartFile uploadedFile = (CommonsMultipartFile) mpr.getFile("reviewImage");
            
            //fileUploadCommand uploadedFile = new fileUploadCommand(params.reviewImg)
            log.debug "ImageController: request params are $params"
            
            def uploadedFile = request.getFile('reviewImg')
            
            if (!uploadedFile?.empty){
              //println "Class: ${uploadedFile.class}"
              //println "Name: ${uploadedFile.name}"
              //println "OriginalFileName: ${uploadedFile.originalFilename}"
              //println "Size: ${uploadedFile.size}"
              //println "ContentType: ${uploadedFile.contentType}"
             
              def webRootDir = servletContext.getRealPath("/")
              def reviewDir = new File(webRootDir, "/images_app/${session.user.login}")
              reviewDir.mkdirs()
              uploadedFile.transferTo( new File( reviewDir, uploadedFile.originalFilename))
            }
      }