Hi Mike,
I don't think so, but it shouldn't be too hard to add support for this. We can add a command-line parameter for the table name and use that instead of extracting it from the filename.
If you feel comfortable working with the code, feel free to give it a try and send a pull request. I can also have a look, I could probably get it done by Monday. It really should only be a ~10 line patch or so.
You could also try to use sed to post-process pgdbf's output, as the table name is not used in many places - if you use the flags: -CDt (don't CREATE TABLE, don't DROP TABLE, use a transaction), then the table name will only be used in the second line of the output (the first line will be 'BEGIN;' to start the transaction). You could replace that like this (where 'mytablename' is the table name you want to use):
for dbf in *.dbf; do
pgdbf -CDt $dbf | sed '2c\\\COPY mytablename FROM STDIN'
done
I haven't tested this, but I think it should work.
Hope that helps,
Philipp