MSNbot visit my site but is it not in the search engine

Hi all,
I have a site four years old that was indexed on MSN 6 month ago.
Now it has been deseapeared from the search engine completly.

The thing is I have two sisters sites and are indexed but the parent not. Any idea.

Parent site:
toibiza.com

Sisters sites:
ToMallorca.com
ToBenidorm.com

Apache log of the parent site:
65.55.211.51 - - [11/May/2008:17:48:45 +0200] "GET /es/ibiza-webcam.html HTTP/1.1" 200 6295 "-" "msnbot/1.0 (+http://search.msn.com/msnbot.htm)"
65.55.213.57 - - [12/May/2008:05:29:58 +0200] "GET /robots.txt HTTP/1.0" 200 171 "-" "msnbot-media/1.0 (+http://search.msn.com/msnbot.htm)"
65.55.213.57 - - [12/May/2008:05:29:58 +0200] "GET /es/hotel/apartamentos-sol-bay-xinxo-cala-bou-port-des-torrent-149.html HTTP/1.0" 200 54825 "-" "msnbot-media/1.0 (+http://search.msn.com/msnbot.htm)"
65.55.213.57 - - [12/May/2008:05:34:33 +0200] "GET /es/ibiza-mapa.html HTTP/1.0" 200 41874 "-" "msnbot-media/1.0 (+http://search.msn.com/msnbot.htm)"
65.55.213.57 - - [15/May/2008:06:01:42 +0200] "GET /robots.txt HTTP/1.0" 200 171 "-" "msnbot-media/1.0 (+http://search.msn.com/msnbot.htm)"
65.55.213.57 - - [15/May/2008:06:01:43 +0200] "GET /en/ibiza-mapa.html HTTP/1.0" 200 39288 "-" "msnbot-media/1.0 (+http://search.msn.com/msnbot.htm)"

Any idea?