Sitemap Download Logs Error When Deleting

When we are looking at our page of sitemaps download logs and go to delete one record or select a page of records to delete we get this error that shows right above the log charts.

Warning: fopen() [function.fopen]: Filename cannot be empty in [path]/vbseo_sitemap/index.php on line 258

Warning: fwrite(): supplied argument is not a valid stream resource in [path]/vbseo_sitemap/index.php on line 259

Warning: fclose(): supplied argument is not a valid stream resource in [path]/vbseo_sitemap/index.php on line 260

Any ideas?