My server crash

Hello,

I have a problem that I don't understand.

Sometime my server crashes and I must restart/start OpManager service. It seems me the problem is caused by the utlization of the java client. For example, when I use the Java client and I forget to exit it after I have used it, the client loses the connection with the server, then a popup message alerts me that I must restart the server (the server has crashed just before).

Anybody could help me to solve that?
Thanks

Regards.