Based on changes in the networking world regarding SSL, many servers are changing their SSL/ TLS supported versions, as well as ciphers/hashing algorithms.
This article is specific to SHA2 use with the ProxySG appliance.
SHA2 is only used in TLS 1.1 and 1.2, typically with either SHA-256 (32 bit) or SHA-512 (64 bit).
SGOS 6.5 supports SHA 2, and works with the SHA-256 and SHA-512 as of 6.5.2.x, including during SSL interception.
If you require the appliance to generate a CSR that uses SHA2, please contact Blue Coat Support for assistance with configuring the appliance.