NFS disconnects and weird behavior

We have an XServe connected to a Solaris box with AFP emulation (Xinet) via an NFS mount (Volumes/Data_Mirror/Ad_01). The XServe is running a web app that needs access to the file system over that mount (think simple content management system – needs to move files around, create new ones, etc.) Every once in a while the web app reports that it’s connection to the NFS mount has disconnected. It’s only for a short period of time and we recover and reconnect, but the logs from the XServe are beyond my ability to figure out what is going one. Any clues would be appreciated.

7/8/10 11:14:32 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:33 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:33 AM configd[29] network configuration changed.
7/8/10 11:14:33 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:35 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:35 AM kernel Ethernet [Intel82574L]: Link up on en0, 1-Gigabit, Full-duplex, Asymmetric Receiving flow-control, Debug [7969,bd48,0de1,0200,c801,3800]
7/8/10 11:14:37 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:37 AM configd[29] network configuration changed.
7/8/10 11:14:37 AM /usr/sbin/serialnumberd[28886] Responding to network change notification.
7/8/10 11:14:41 AM kernel nfs server brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01: not responding
7/8/10 11:14:46 AM com.apple.DirectoryServices[26] Enter machine password:
7/8/10 11:14:48 AM com.apple.loginwindow[85] 2010-07-08 11:14:48.068 ManagedClient[41446:903] ODUGetMCXRecordWithCache() Accessing network user record from Active Directory not allowed because no authentication information was supplied.
7/8/10 11:14:48 AM com.apple.loginwindow[85] 2010-07-08 11:14:48.070 ManagedClient[41446:903] MCX.gatherUserInfoFor: ODUGetRecordGroups( svccadre )) returned no information == 0 ((null))
7/8/10 11:14:48 AM com.apple.loginwindow[85] 2010-07-08 11:14:48.070 ManagedClient[41446:903] MCX.recompositePrefs – user record could not be located
7/8/10 11:14:49 AM com.apple.DirectoryServices[26] DNS update failed!
7/8/10 11:14:57 AM com.apple.loginwindow[85] 2010-07-08 11:14:57.147 ManagedClient[41458:903] ODUGetMCXRecordWithCache() Accessing network user record from Active Directory not allowed because no authentication information was supplied.
7/8/10 11:14:57 AM com.apple.loginwindow[85] 2010-07-08 11:14:57.149 ManagedClient[41458:903] MCX.gatherUserInfoFor: ODUGetRecordGroups( svccadre )) returned no information == 0 ((null))
7/8/10 11:14:57 AM com.apple.loginwindow[85] 2010-07-08 11:14:57.149 ManagedClient[41458:903] MCX.recompositePrefs – user record could not be located
7/8/10 11:15:04 AM kernel nfs_connect: socket connect taking a while for brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01
7/8/10 11:15:48 AM kernel nfs_connect: socket error 60 for brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01
7/8/10 11:15:48 AM kernel nfs_connect: socket connect aborted for brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01
7/8/10 11:15:48 AM kernel nfs server brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01: can not connect, error 60
7/8/10 11:15:48 AM kernel nfs server brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01: is alive again
7/8/10 11:15:48 AM kernel nfs server brppsad01.hhshoppers.net:/Volumes/Data_Mirror/Ad_01: connected