CA does not provide a specific BOXI agent for SSO, however there is solutions available.
BOXI comes with an integrated SiteMinder custom agent to provide easy integration. This is actually a 4.x compatible agent built using the SiteMinder SDK. For more details please review the Deployment Guide.
BOXI also supports Trusted Authentication. This requires BOXI user accounts to be the same as the SiteMinder account being passed in the specific header value. A standard SiteMinder Web Agent would protect the front end web server. For more details please review the Deployment Guide.
BOXI Deployment Guide can be found here: http://help.sap.com/businessobject/product_guides/boexir2/en/xir2_bip_deploy_en.pdf.
Important! Please note that these are not CA supplied or supported solutions. We can help troubleshoot the relevant SiteMinder logs, but support should be sought from SAP.