Banks may now use their own home loans - rather some other banks home loans - in repurchase agreements with the Reserve Bank of Australia.When the RBA widened the eligible collateral for repurchase agreements to include mortgage-backed securities late last year the RBA wrote the rule to oblige banks to first buy the RMBS securities of other issuers in order to use them in repo activities.So while most banks arranged internal securitisations of a portion of their home loan book (on top of any sold to outside investors during the credit boom) those RMBS assets did not qualify for repo except in exceptional circumstances.There appears to have been a shortage of repo-eligible assets for banks over the last week or two, with the banks making greater use of RMBS in any event.