Error importing vmdk files using ec2 developer tools

Although vmdk disk format is supported by ec2-import-instance tool, every time I try to run the command on a vmdk file, I get the following error:

    ERROR: File uses unsupported compression algorithm 0

I invoke the tool in the following format:

    ec2-import-instance -f vmdk -o <ACCESS KEY> -w <SECRET KEY> <VMDK file>

I am using ec2 tools version 1.6.6.1.

Solution

Looks like it's got nothing to do with "compression algorithm" but instead more to do with supported vmdk formats as documented in http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/VMImportPrerequisites.html