Using current CVS HEAD of geo on drupal 6.19 with MySQL.

If I create a Geospatial data field with a widget type of Latitude/Longitude then when I save the page I get the following warning:

warning: mb_strlen() expects parameter 1 to be string, array given in /var/www/vhosts/mysite/includes/unicode.inc on line 404.

If I do a var_dump() of parameter 1 at that point it is:

array
'lat' => string '' (length=0)
'lon' => string '' (length=0)