Property:Foaf:mbox sha1sum

From semanticweb.org

This attribute represents the property foaf:mbox_sha1sum (Friend Of A Friend) , "imported" into SMW by the special mapping MediaWiki:smw_import_foaf. This publishes a hash for someone's email address without revealing the address to spammers. The SHA1-hash needs to be generated externally with some appropriate tool.

[edit] Test

Let's try restricting values of this imported property to:

a, b, 7074170ebe54951b0bf4d8d8f5dcc5014c53bed1