URL returned error: 500 when sending key to server

[Daniel Stöckner]

Hello,

I created a standard key-pair for my mail-address. When trying to send
the key to one of the servers with:

gpg -v -v --keyserver subkeys.pgp.net --send-key <my key-ID>

I get the following message:

gpg: sending key <my key-ID> to hkp server subkeys.pgp.net
gpgkeys: HTTP post error 22: The requested URL returned error: 500

It is again and again reproducible.
Does that mean "Internal Server Error" as with http? I don't know what
to do about this or even if I can do anything about this. I haven't
found any solution here or with google. Any hint greatly appreciated!
Thanks in advance!

-Daniel Stoeckner