I have one of the remote admins using the java client saying that the client logs her out after a few minute, is there a way to extend this log out time?

For java client, yes, you can set the console to never timeout but it affects all users

Admin page >> Servers >> select your site and click Edit Site properties

Set the console timeout to Never or up to 1 hour, you can go with what you need

See here for tips on doing it for the web based browser login:

How to extend the timeout on the SEPM Web based console

increase the timeout , check this discussion

http://www.symantec.com/connect/articles/how-change-default-web-console-time-out-settings-through-sepm

How to extend the timeout on the SEPM Web based console