When deleting a file with a '%' characer, the filename is passed straight to *_strdup_printf(), which causes the %'s to be used in the function, and thus causing a segfault. The %'s need to be escaped with another %.
Looks like bug #1704, which was already fixed after beta1. You can use the patch with beta1 in the meantime. *** This bug has been marked as a duplicate of 1704 ***