I try to debug an application server (WebLogic) with IntelliJ IDEA 11.1 Ultimate. The debugger configuration worked previously, I didn't change anything.
What happens is: IntelliJ tells me
Connected to the target VM, address: '[snip]:9009', transport: 'socket'
Okay, solved it: I had a method breakpoint active. Apparently that slowed the whole debugging process down so much that I couldn't interact with the debugger. Once I removed the breakpoint, debugging worked again.