Cannot import private key into gpgsm

[ckeader]

> One source said that gpg and gpgsm share the same database at least
> for private keys.  But I get an import error trying to import the
> PEM file with only the key into gpg.
> 
> How can I successfully import the certificates and the key into
> gpgsm?

FWIW, I've never been able to import the S/MIME cert from $WORK into
gnupg/gpgsm straight. I've had to go via thunderbird import -> export > gpgsm
import to become functional. Not sure why, maybe CRLF was an issue, but
I never investigated as I have a working process.