hello, I solved it for real, as asked.
I copied the System icons for guest user, converted them to tiff, and packed them with instructions, basically adding them to the user icons folder.
It needs to be known to people that the user login picture you have for OS X is used for your adress book. Changing the icon in iChat for example to the mobileme-cloud didn't affect the one in address book, nor the login one for OS X. It is a useful request to have a system wide option in the accounts Preferences (IMHO) to set the desired picture once and for all system wide and for internet visibility (iChat)
Here you go:
http://www.mediafire.com/?sharekey=a1e65604ad3eca64d2db6fb9a8902bda
To me it's a shame to call this thread solved, and I cannot help by posting there:
http://discussions.apple.com/thread.jspa?threadID=1331819