Thumbnail size - Java Uploader

Im trying upload 2 different thumbnal size.

iu.addParam("UploadThumbnail1FitMode","fit");

iu.addParam("UploadThumbnail1Width","120");

iu.addParam("UploadThumbnail1Height","120");

iu.addParam("UploadThumbnail1JpegQuality","75");

iu.addParam("UploadThumbnail2FitMode","fit");

iu.addParam("UploadThumbnail2Width","800");

iu.addParam("UploadThumbnail2Height","800");

iu.addParam("UploadThumbnail2JpegQuality","45");

under WINXP IE6 working ok.

But under WINXP Firefox 2.0.0.4 I cannot get second thumbnail size 800px but its maximum width 160px.

version

// ActiveX

iu.activeXControlVersion = "3,5,100,0";

// Java Applet

iu.javaAppletVersion = "1.1.60.0";

iu.javaAppletCached = true;

Thanks

Marcel