[vchkpw] problems with rbls?

[Brendan McAlpine]

Does anyone know if any of the following rbls are slow or non-functional?

Starting at about 2PM EST, my smtp concurrency shot through the roof, which is usually a sign that one of the rbls i am using isn't working properly. anyone know of any problems with the following rbls:

korea.services.net
relays.ordb.org
relays.osirusoft.com
sbl.spamhaus.org
spews.relays.osirusoft.com

If nothing is wrong, any reason why my smtp concurrency would shoot up to its maximum? I am watching the smtp log roll by and it doesn't seem to be an attack from any one address......

TIA

Brendan