GPG and 1024-bit (or multiple) subkeys

[Charles Franklin Bernard]

New to list; first post.
We send member companies our 1024 bit public key with its 1024-bit
subkey to encrypt their A/R files before they're FTP'd to us.  A new
customer is requesting we generate a new key for them that has a 2048
sub key, claiming GPG requires this by default.  So I added another
subkey, 2048-bit, but the customer says GPG is looking for a 2048
subkey *by itself*.  Does that make sense?  Doesn't GPG have an easy
programmatic way to specify a subkey and/or bit size?

Thanks,
Frank