This question has already been answered, but the Download does not work. Please help me too 
automatic resizing to current tab content
I came across this piece of advice:
dhtmlXTabBar.prototype.adjustSize=function(){
if ((!this._ahdj)&&(!this._awdj)) return;
var flag=false;
var x=0;
var y=0;
for (var id in this._content){
Marked code loop through all existing tabs, you can modify it to use only current active tab, and call in from OnSelect event handler
- can You give an example, please?