How to load custom jar in Zimbra Server?

[Mansic03]

I have overwritten the code of the FileUploadServlet.class (\com\zimbra\cs\service\FileUploadServlet.class) of the zimbrastore.jar file. The new class has packaged it into a new jar file -> myCustomJar.jar

How can I do Zimbra load my myCustomJar.jar file and not use the FileUploadServlet.class class of the zimbrastore.jar file but use the FileUploadServlet.class class of myCustomJar.jar?

One way to do this is to do that the last Jar to be loaded be myCustomJar.jar, but I don't know how to do this.

I appreciate your help.
Thank you.