The attach Screenshot functionality not working with Java 7u51. This is a known issue with Java 7u51. Per the last message Atlassian is missing some attributes in their manifest file.

We had the same issue. To get out stuff to work after this change, and as an FYI potentially to Atlassian, our manifest (META-INF/MANIFEST.MF) changed from this:

Manifest-Version: 1.0
Trusted-Library: true
Created-By: 1.6.0-internal (Sun Microsystems Inc.)

To this:

Manifest-Version: 1.0
Trusted-Library: true
Created-By: 1.6.0-internal (Sun Microsystems Inc.)
Permissions: all-permissions
Codebase: *
Application-Library-Allowable-Codebase: *
Caller-Allowable-Codebase: *
Application-Name: iGrafx Applet

Obviously, they would need to change the application-name. We probably need a couple of permissions they don’t – but it was a pain to figure this out.