I went into the JSDK 2.1 main directory. There should be two jars there, server and servlet. I broke these out and recombined them into one big jar called jsdk.jar (basically just copy the larger of them, call it jsdk.jar, then break out the other and add it to jsdk.jar using WinZip). Then I installed Apache JServ normally.

I think the following might also work equally well: Make a temporary jsdk.jar file in that directory (it can be empty if you like). When the Apache JServ installer asks you for the location of jsdk.jar, give it this directory. (The reason you need to do this at all is that the installer won't let you past this question otherwise.) After everything is installed, edit the jserv.properties file. Look for the wrapper.classpath properties. Apparently you can have more than one of these (you'll have two as it is), so it should be no problem to replace the line containing jsdk.jar with two containing server.jar and servlet.jar.

For all I know, jsdk.jar is used somewhere else, so beware. In any case, if you have no JSDK installed already, I'd just stick with 2.0 for now.
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