ssh-agent and PCKS#11 keys

I tried this with 1Password's ssh agent. As you can see it failed. If using a regular old ssh agent it will succeed. Is there some other way to get this key into 1Password's ssh agent?

$ ssh-add -s /usr/local/lib/opensc-pkcs11.so
Enter passphrase for PKCS#11:
Could not add card "/usr/local/lib/opensc-pkcs11.so": agent refused operation