DHTMLX tree+check box

Respected Sirs, 

Is there any method or xml attribute for changing the image of  a particular check boxe in dhmlx tree, dynamically for a perticular action.  I am using  dhmlx tree version 6 (standard edition). If  there is no solution directly ,can we modify some of standard methods in sourcesode ,for do this.




The image can’t be changed by API call ( you can change only state - checked|unchecked|disabled etc. )
The code to change tree item directly by DOM manipulation will look as
    tree._idpull[id].htmlNode.childNodes[0].childNodes[0].childNodes[1].childNodes[0].src=“custom image path”;

id - id of item