Env : DB2 UDB 8.2, AIX 5.3, Ascential Datastage (DS)

DS jobs are used to process the backend DB2 database. Sometimes DS job
fails with the message
APT_CombinedOperatorController,0: Fatal Error: Fatal: [IBM][CLI Driver]
SQL1224N  A database agent could not be started to service a request,
or was terminated as a result of a database system shutdown or a force
command.  SQLSTATE=55032
Unable to connect to DB2 server 'oipdb'.

But at the same time when I try to connect from AIX prompt (local
client) connection is successful.

Following are some related settings in my dbm

db2inst2 /home/db2inst2 > db2 get dbm cfg | grep MAX
Max number of existing agents               (MAXAGENTS) = 400
Max number of coordinating agents     (MAX_COORDAGENTS) = (MAXAGENTS -
NUM_INITAGENTS)
Max no. of concurrent coordinating agents  (MAXCAGENTS) =
MAX_COORDAGENTS
Max number of client connections      (MAX_CONNECTIONS) =
MAX_COORDAGENTS
Number of pooled fenced processes         (FENCED_POOL) =
MAX_COORDAGENTS
SPM resync agent limit                 (SPM_MAX_RESYNC) = 20
Maximum query degree of parallelism   (MAX_QUERYDEGREE) = ANY
Max number of node connection retries (MAX_CONNRETRIES) = 5
Max time difference between nodes (min) (MAX_TIME_DIFF) = 60

db2inst2 /home/db2inst2 > db2 get dbm cfg | grep NUM_INITAGENTS
Initial number of agents in pool       (NUM_INITAGENTS) = 0
Max number of coordinating agents     (MAX_COORDAGENTS) = (MAXAGENTS -
NUM_INITAGENTS)