it is possible to integrate Knowledge Base?
Probably not. The reasoning is that if would take a lot of development to make he best Knowledge Base program available. So we would recommend that you should use the best available.
So yes you would have to cut and paste responses from ADefHelpDesk into the other program, but you could offer your users the best possible program when they are searching for answers in your Knowledge Base.
What we strive to do is to create the BEST HelpDesk/Ticket Tracker module available. At this time we do not see a Knowledge Base as being vital to resolving a issue that has been submitted.