Quoting from the rPath official announcement:
rPath™, provider of a platform for creating and maintaining virtual appliances, today announced that virtual appliances intended for the VMware Virtual Appliance Marketplace can be developed using the rPath Appliance Platform to automate some of the certification requirements of the VMware Virtual Appliance Certification Program.
In addition to complying with VMware best practices for developing virtual appliances, virtual appliance developers can now add the VMware Tools package, which is required for certification, directly inside the virtual machine using rBuilder.
After the virtual appliance has been created using rBuilder, a developer can submit it to VMware for certification. In addition, a developer can automatically publish an uncertified virtual appliance from rBuilder to the Community section of the VMware Virtual Appliance Marketplace.
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rPath is currently running an Application to Appliance Program to convert qualified commercial Linux-based software applications into virtual appliances at no charge…