I'm having a problem with sending a serialized object to a servlet and I'm hoping someone can help me out. The error i'm getting is: java.io.InvalidClassException: com.hsssi.rda.client.Session; Local class not compatible: stream classdesc serialVersionUI=-670601590654791455 local class serialVersionUID=0 I'm compiling using jbuilder, then copying the class files into the WEB-INF directory, so i see no reason why they would be different versions. On another note, I'm getting some very inconsistent results using URLConnection.getInputStream() after I do me post. This occures after I post the object stream to the servlet and then try to read a output from the servlet. When I access a perl cgi it works fine, but when I access a servlet I'm getting a FileNotFound io exception. Any ideas on either of these two? its driver me crazy. Oh, jvm is 1.3, apache is on Solaris, app is running from win98 Thanks, Jeff