Hello, You can set the pool size for MDB in the following file on jboss. At standardjboss.xml file in the path, <JBOSS_HOME>/server/all/conf/standardjboss.xml 189 <invoker-proxy-binding> | 190 <name>message-driven-bean</name> | 191 <invoker-mbean>default</invoker-mbean> | 192 <proxy-factory>org.jboss.ejb.plugins.jms.JMSContainerInvoker</proxy-factory> | 193 <proxy-factory-config> | 194 <JMSProviderAdapterJNDI>DefaultJMSProvider</JMSProviderAdapterJNDI> | 195 <ServerSessionPoolFactoryJNDI>StdJMSPool</ServerSessionPoolFactoryJNDI> | 196 <CreateJBossMQDestination>true</CreateJBossMQDestination> | 197 <!-- WARN: Don't set this to zero until a bug in the pooled executor is fixed --> | 198 <MinimumSize>1</MinimumSize> | 199 <MaximumSize>15</MaximumSize> | 200 <KeepAliveMillis>30000</KeepAliveMillis> | 201 <MaxMessages>1</MaxMessages> | 202 <MDBConfig> | 203 <ReconnectIntervalSec>10</ReconnectIntervalSec> | 204 <DLQConfig> | 205 <DestinationQueue>queue/DLQ</DestinationQueue> | 206 <MaxTimesRedelivered>10</MaxTimesRedelivered> | 207 <TimeToLive>0</TimeToLive> | 208 </DLQConfig> | 209 </MDBConfig> | 210 </proxy-factory-config> | 211 </invoker-proxy-binding> Hope, this might solve your problem. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3996374#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...