errors about certificates during install/update kernel

>Description of problem:

during `yum install vzkernel` or `yum update` I see now

```
# yum update
...
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : vzkernel-devel-2.6.32-042stab123.9.x86_64 1/2
  Installing : vzkernel-2.6.32-042stab123.9.x86_64 2/2
curl: (60) Peer certificate cannot be authenticated with known CA certificates
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
 of Certificate Authority (CA) public keys (CA certs). If the default
 bundle file isn't adequate, you can specify an alternate file
 using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
 the bundle, the certificate verification probably failed due to a
 problem with the certificate (it might be expired, or the name might
 not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
 the -k (or --insecure) option.
Invalid UUID , aborting
  Verifying : vzkernel-2.6.32-042stab123.9.x86_64 1/2
  Verifying : vzkernel-devel-2.6.32-042stab123.9.x86_64 2/2

Installed:
  vzkernel.x86_64 0:2.6.32-042stab123.9 vzkernel-devel.x86_64 0:2.6.32-042stab123.9
```


>Expected results:

Errors about certificates should not happen

>Host OS:
latest Centos 6