server reports bogus maxSpool > Max group numbers

I'm getting this error on 6.41B4:
[16:24:08] ERROR - Server:<server>Server Reports bogus MaxSpool > MaxGroup Numbers :368838354:2735137387 - <group name>
I get loads of these on various groups.
[16:24:08] ERROR - Server:<server>Server Reports bogus MaxSpool > MaxGroup Numbers :368838354:2735137387 - <group name>
I get loads of these on various groups.