Help with JSESSIONID persistence

Sorry for long post but I think I am missing something here and got no clue somehow my persistence is not configured properly, here is the exact irule I am using

 
when HTTP_REQUEST {
set uri [ HTTP::uri ]
if { $uri contains "myapp" } {
 find out if session id is defined
set sessionId [ HTTP::cookie "JSESSIONID" ] 
log "request for $uri , when sessionId is -- $sessionId "
if { $sessionId == "" } {
 look for auth cookie
set authCookie [ HTTP::cookie "auth" ]
set location [HTTP::cookie "server_location" ]
if {  $authCookie != "" and $location != "" } {
if { $location equals "myapp" } {
    pool appserver_pool
    } 
    }
else {
    HTTP::redirect "http://10.0.0.1/auth/"
    }
    } else {
persist session
persist uie $sessionId 3600
set location [ HTTP::cookie "server_location" ]
 log "SessionId not null location is $location " 
 if { $location equals "myapp" } {
pool appserver_pool
 }
    }
    }
elseif { $uri contains "auth" } {
log "request for $uri , when no session JSESSIONID is [HTTP::cookie "JSESSIONID"] "
pool authserver_pool
    }
}
when HTTP_RESPONSE {
  HTTP::header replace "Server IP" [ IP::server_addr ]
  log "Server Address [IP::server_addr] "  
  set sessionId [ HTTP::cookie "JSESSIONID" ]
  if { $sessionId ne "" } { 
   log "app server has set JSESSIONID $sessionId add persistence"
    persist off session id for an hour (3600 seconds)..
   persist add uie $sessionId 3600 
  }
}

My virtual server has authserver_pool as its default pool. appserver_pool has two nodes. Virtual server has http profile only. everything else is default. On an average I receive HTTP request in every 15 seconds from same client. And log shows this :

 
Wed May 5 01:11:23 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.1
Wed May 5 01:11:23 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331
Wed May 5 01:11:10 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.1
Wed May 5 01:11:09 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331
Wed May 5 01:10:56 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.2
Wed May 5 01:10:56 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331
Wed May 5 01:10:43 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.2
Wed May 5 01:10:43 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331
Wed May 5 01:10:30 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.2
Wed May 5 01:10:30 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331
Wed May 5 01:10:17 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _persist_sessionId_on_resposne : Server Address 192.168.1.1
Wed May 5 01:10:17 PDT 2010 info local/tmm tmm[4117] 01220002 Rule _validate_request : request for /myapp/poll , when sessionId is -- C195535A841C7D81985E33F2DFA51331

I am not sure why request goes to 2nd node when I am persisting session for an hour. Someone plzzzzzzzzzz help me. I have no clue here. I would greatly appreciate your help.