UI Drag and Drop by click

UI Drag and Drop by click

Hi all,
spent some hours to my next problem:
I have a div with an image:
<div id='pos6-3'><a href='JavaScript:squareClicked(6, 3, true)'><img
name='pos6-3' src='images/knight.gif' height="45" width="45"
border='0' alt='blank'></img></a></div>
I want to drag this into another div by clicking the first square and
then drop it in another div by clicking on that second div,
( replacing the old image their )
second div looks something like:
<a href='JavaScript:squareClicked(4, 1, true)'><div id='pos4-1'><img
name='pos4-1' src='images/blank.gif' height="45" width="45" border='0'
alt='blank'></img></a></div>
So when i click on knight.gif and then click on blank.gif,
blank.gif must be replaced by knight.gif.
And of course on the original location of knight.gif, blank.gif must
be placed.
How do i move this image by clicking only?
Many thanks in advance for every single word, which pushes me in the
right direction!
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