[Users] Cannot upload iso

[Mario Giammarco]

Hello,
I am using ovirt 3.1
I do:

engine-iso-uploader  -v -i ISO list

and I get:

Please provide the REST API password for the admin at internal
 oVirt Engine user 
(CTRL+D to abort): 


I insert correct password but I get:

ERROR: [ERROR]::ca_file (CA certificate) must be specified
 for SSL connection.
INFO: Use the -h option to see usage.


I do not want to use certificates, only passwords. And, 
in my setup, uploading an 
ISO is not a security breach.

What can I do?

Thanks,

Mario