FileIsTooLargeText test doesnt appear

FileIsTooLargeText text doesnt appear even when the Image is more than MaxFileSize.

I am using ImageUploader Version 5.1 it used to appear in 4.5 version.

var iu = new ImageUploaderWriter("ImageUploader", 764, 290);

iu.addParam("PaneLayout", "TwoPanes");
iu.addParam("AllowRotate", "true");
iu.addParam("BackgroundColor", "#ffffff");
iu.addParam("ButtonSendText", ""); //hide send button
iu.addParam("FolderPaneShowDescriptions", "false");
iu.addParam("CheckFilesBySelectAllButton","true");
iu.addParam("MessageUploadCompleteText", "");
iu.addParam("ButtonStopText", "");

//file exts
iu.addParam("FileMask", "*.jpg;*.bmp;*.gif;*.tiff;*.png");

//upload settings
iu.addParam("FilesPerOnePackageCount", "1");
iu.addParam("MaxFileCount", 9553);
iu.addParam("MaxFileSize", 5242880);
iu.addParam("MinImageHeight", "1");
iu.addParam("MinImageWidth", "1");

//upload thumbnail settings
iu.addParam("UploadThumbnail1CopyExif", "true");
iu.addParam("UploadThumbnail1CopyIptc", "true");
iu.addParam("UploadThumbnail1FallbackMode", "SourceFile");
iu.addParam("UploadThumbnail1FitMode", "Width");
iu.addParam("UploadThumbnail1JpegQuality","90");
iu.addParam("UploadThumbnail1Width", "600");
iu.addParam("UploadSourceFile", "false");

//thumbnail
iu.addParam("PreviewThumbnailBorderColor", "#cecfce");

But I dont want the edit descriptions option available. I want the users only to see the red warnings and not edit the descriptions. Is there a way I can do that.

Thanks