hostname checksum illegal

Hi --

I keep seeing the following two lines in my mail log file:

May 10 12:55:11 is1 dccm[55813]:
/var/dcc/userdirs/local/[REDACTED]/whiteclnt.dccw is a global
whitelist used as a per-user whitelist

May 10 12:55:11 is1 dccm[55813]: hostname checksum illegal in line 5
of /var/dcc/userdirs/local/[REDACTED]/whiteclnt

And I honestly don't know what to do about either one of them. There's
nothing obviously different about that user's whiteclnt compared to
the others, at least not that I see. So what could make it appear to
be a global whitelist?

I've deleted the whiteclient.dccw file a few times, in the hope that a
rebuilt one would be OK, but that hasn't helped.

Thanks for any suggestions or illumination on this.

-- John