To get an idea of what you can do in this area, have a look at our web site http://www.sjsoft.com where we have branches to various different instances.

For example, you can go to the Logbook demo as the user admin by clicking on the link next to the man diving off the bridge. Here the link says http://demo.sjsoft.com/demo/index.htm?username=admin&islogin=1 and we have made it so that the user doesn't even have to log in. I.e. the username and password are embedded into the link.

A little lower down, there is the example of the "Full Function Demo" Here the link says:
http://demo.sjsoft.com/demo/
In this case, the user is required to enter the user name and password since it is not defined in the command line. (please note the trailing /)

Essentially, since this is a stateless system, most of the functions such as filters etc. Can be embedded in the URL.

There is also a web page in the system administration manual which covers this:
http://www.sjsoft.com/docs/jlogbook/admin/menupage.htm

If you would like a customized log-in page, you can also create this. There is an example of one and a description of how you can do this at this page:
http://www.sjsoft.com/docs/jlogbook/admin/htmllogon.htm
Essentially, the required arguments are either input fields or hidden fields.