From the FAQ:
[Q:] Is there a limit to the amount of applications allowed to be signed with a Code Signing Certificate?
[A:] Comodo does not limit you to any specific number. You can sign as many applications with a Code Signing Certificate as you wish, provided that the applications are going to be used for and distributed by the Organization that owns the certificate.
I want to distribute a signed redistributable DLL. Is this possible under Comodo's terms of service?