Dashboard widget drag'n'drop breaks after first use

After I try to move a widget on the dashboard, the drag'n'drop feature just stops working without any errors.

Broken by

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r38681 | eduards | 2013-09-20 16:15:54 +0300 (Fri, 20 Sep 2013) | 1 line
Changed paths:
M /trunk/frontends/php/js/class.pmaster.js
M /trunk/frontends/php/js/flickerfreescreen.js
M /trunk/frontends/php/js/gtlc.js
M /trunk/frontends/php/slides.php

..F....... ZBX-3878 fixed memory leaks in slide show
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