Please set the "org.mortbay.http.HttpRequest.maxFormContentSize " system property.
You can use the [MWS Install Directory]/server/default/config/portal.properties file to configure system properties.
So you could set the maxFormContentSize to a little less than 1 MB by adding the following line to portal.properties (and restarting mws):
org.mortbay.http.HttpRequest.maxFormContentSize = 1000000
Please let me know if this help.
#webMethods#webMethods-BPMS#MWS-CAF-Task-Engine