[Plugin: nice-map] Errormessage

In addition to the geo-mashup plugin, i have installed the nice-map plugin, which should improve the appearance of maps on my blog.

To make use of the geo-mashup plugin, i use the shortcode [geo_mashup_map], which works, as it should. However if I use the shortcode [nicemap] instead, to make use of the nicemap-pugin, i get the following error message:
Warning: implode() [function.implode]: Bad arguments. in …/wp-content/plugins/nice-map/nicemap.theme.php on line 143

Warning: implode() [function.implode]: Bad arguments. in …/wp-content/plugins/nice-map/nicemap.theme.php on line 144

that is the code of the two lines:

$options['layers'] = implode(',', $options['layers']);
  $options['styles'] = implode(',', $options['styles']);

The WP-version I use is 2.8.2, but it did not work either before I upgraded from 2.7. The PHP version I use is 5.2.0

Any ideas how i could fix this?

Thx,
Jakob