> *http://130.89.152.133:8888/docsNL/uploads/110/htmlalgemeen.gif* 
> It works, but it is absolut and sensitiv when I migrate to another server or
> even change the port

You could do several things. First, there are non-page specific uploads. 
So, if you had upload htmlalgemeen.gif there, you would be able to reach 
it from both pages.

Secondly, *http:/docsNL/uploads/110/htmlalgemeen.gif* will work 
regardless of port or server.

Peace and Luck!

Je77