node status flags -- where are they documented?

[Derrell.Lipman at UnwiredUniverse.com]

I am modifying nmblookup to provide an easily script-parsable output format.
I'd like to (at least marginally) document the output, but I can't locate
anyplace that describes what the node status flag bits actually mean.  The CVS
version nmblookup displays single letters for representing four of the bits.
What do these mean?

                fstrcat(ret, (flags & 0x80) ? "<GROUP> " : "        ");
                if ((flags & 0x60) == 0x00) fstrcat(ret,"B ");
                if ((flags & 0x60) == 0x20) fstrcat(ret,"P ");
                if ((flags & 0x60) == 0x40) fstrcat(ret,"M ");
                if ((flags & 0x60) == 0x60) fstrcat(ret,"H ");
                if (flags & 0x10) fstrcat(ret,"<DEREGISTERING> ");
                if (flags & 0x08) fstrcat(ret,"<CONFLICT> ");
                if (flags & 0x04) fstrcat(ret,"<ACTIVE> ");
                if (flags & 0x02) fstrcat(ret,"<PERMANENT> ");

What do B, P, M, and H stand for?

Thanks,

Derrell