Glassfish doesn't load jdbc

I've a application in swing and ej开发者_Go百科b3 inside glassfish v2ur2 and until one week ago all was ok. in sometime, the glassfish never more load the jdbc driver of postgresql and the connection with the bd fail, but the jdbc driver is in the project and in the classpath. the only way to fix it was put the jar inside lib folder of glassfish domain....

know anybody what's happening?

If you're using a container managed DataSource, then the JDBC driver needs to be in the classpath of the container itself (appserver/lib), not of the webapplication (WEB-INF/lib).