You can get your server certificate on https://tcs.cesnet.cz/.
On July 1st 2015 there will be a new supplier of TCS certificates - DigiCert company. After this date, the certificates will be issued under this root only.
From the reasons specified above, it will be no longer possible to issue new TCS certificates under the old Comodo root after 2015-07-01. Existing certificates remain valid (until the expiration or revocation).
TCS certificate portal can't issue the SHA1 certificates nowadays. If you are sure you want a SHA1 certificate, please contact us at email@example.com. Certification chains for SHA1 certificates remained the same. Certification chains and CRLs are below.