New Blog Template not copying widgets in sidebars

I am creating a multisite installation, and I want all new blogs to have a default set of sidebar widgets. I don't want to hardcode these, as I don't want them to be overwritten when users add new widgets to their sidebars.

I have installed the New Blog templates plugin, and it seems to be copying everything else except for the widgets in the sidebar.

Instead, my sidebars show up with the error:

Warning: array_key_exists() expects parameter 2 to be array, boolean given in C:\xampplite\htdocs\wp-includes\widgets.php on line 858

and the standard wordpress widgets (search, meta, e.t.c)