duplicate preload-node hiding content

[gerpres]

I'm displaying a dgrid in a contentpane in a border-container.

there're about 30 rows in the grid. via store.notify, those rows are removed after some time.

if the grid is empty, I remove the contentpane from the border-container to hide the grid.

if the dgrid's store gets notified of new content, the grid._onNotification() callback is triggered. then I re-add the contentpane to the border-container.

the new row(s) exist in the DOM, but aren't displayed, because it's hidden behind a preload-node (dgrid-preload). in fact, there are two preload-nodes in the grid.

if I remove the large preload-node via firebug, everything is fine.
I don't exactly know, where the second preload-node is created.

[gerpres]

just found out what's the actual problem - it's not hiding/showing it again, but if all rows are removed via notify(), adding a new row again via notify() inserts it after the second dgrid-preload node, not between them.