Route-lookup for x.x.x.x yielded reject NH

Hi all,

I'm having some issues with traffic through an SRX3600 cluster.  The traffic is between Active Directory servers in two different zones on directly connected subnets.  Looking through a traceoptions capture I find the following:

Jan 26 11:05:10 11:05:10.436369:CID-01:FPC-08IC-00:THREAD_ID-24:RT:Route-lookup for 10.64.0.72 yielded reject NH

Jan 26 11:05:10 11:05:10.436391:CID-01:FPC-08IC-00:THREAD_ID-24:RT:flow_ipv4_firstpath_route_lookup: no route to dest 10.64.0.72

Jan 26 11:05:10 11:05:10.436417:CID-01:FPC-08IC-00:THREAD_ID-24:RT: jsf drop pak pid 20, jbuf 0x8e869b90, release hold 0, sess_id 0

Jan 26 11:05:10 11:05:10.436442:CID-01:FPC-08IC-00:THREAD_ID-24:RT:[JSF] set ext handle 0x0 for plugin 20 on session 1069446912804

Jan 26 11:05:10 11:05:10.436459:CID-01:FPC-08IC-00:THREAD_ID-24:RT: After jsf gate hit. sid 0xdb24, pid 20, cookie 0x37, jbuf 0x8e8643d0. rc = 16

Jan 26 11:05:10 11:05:10.436481:CID-01:FPC-08IC-00:THREAD_ID-24:RT: packet dropped, denied by gate_hit callback

Jan 26 11:05:10 11:05:10.436491:CID-01:FPC-08IC-00:THREAD_ID-24:RT:denied by gate_hit callback

And I'm not sure what it all means.  10.64.0.0/22 is a directly connected subnet:

10.64.0.0/22 *[Direct/0] 22:29:16
> via reth50.0

Anyone know what the "Route lookup... yeilded reject NH" and the "denied by gate_hit callback" messages are referring to?

Thanks in andvace for any help!