Even I am facing the same problem on WebSphere 5.0.2 running on AIX, that I am not able to upload file of 100KB size if I upload from internet. However if I upload through intranet I am able to upload 120MB file as well. I am getting the following error when uploaded through internet. Please let me know if you have found any solution.
[3/24/06 12:31:22:445 CET] 487c7a3e CommonsMultip E org.apache.struts.upload.CommonsMultipartRequestHandler TRAS0014I: The following exception was logged org.apache.commons.fileupload.FileUploadException: Processing of multipart/form-data request failed. Read timed out at org.apache.commons.fileupload.FileUploadBase.parseRequest(FileUploadBase.java(Compiled Code))