Eucalyptus Cloud 5.1 has been released with important compatibility and functionality fixes and is recommended for all 5.x deployments.
Fixes of note in this release are:
- CloudFormation AWS::IAM::InstanceProfile add InstanceProfileName property
- ELB cannot connect to https listener
- S3 support for multipart copy
- Web services HTTPS (TLS) should use larger ephemeral Diffie-Hellman key size
You can find the full list of resolved issues in the release notes / milestones.