Eclipse does not start incremental build

I am using Eclipse Galileo, JRebel for rapid deployment, and JBoss 5.1.x as my application server. Eclipse has started to behave strangely recently, maybe after switching to a new workspace (only difference from branch to trunk).

Previously, whenever I made changes to the *.java

/ file *.jsp

, JRebel collects the recently changed file .class

for hot deployment.

But now it runs full build instead of incremental build, all projects build instead of one .class update and take a long time. Sometimes the server will crash due to JRebel trying to deploy all updated files *.class

.

Does anyone have an idea why Eclipse is running a full build instead of an incremental build when the file is saved?