Console broken - not showing prompt

Hi all,

I’m having some fun with my console which is starting to get a little
frustrating. When I start the console I get the usual “Loading
development environment” message, but the prompt never appears. After a
couple of seconds I can type in the console, but when I press enter the
input is simply echoed. The problem occurs no matter which environment I
try to load.

I can run the console for other apps on the same machine, so it doesn’t
seem to be a ruby problem, just something gone wacky with that

Any ideas of a sensible place to start digging?