Are you currently using Capistrano 1.4.1? If so, drop everything (I mean it, do this RIGHT NOW) and install Capistrano 1.4.2.
Why, you ask?
Capistrano 1.4.1 will work just fine, right up until you decide you want to experiment with Capistrano 2. When you do that, Cap 2.3+ will install net-ssh 2.x, which kills Capistrano 1.4.1 in all kinds of really obscure ways.
The good news is that Cap 1.4.2 is completely compatible with Cap 1.4.1. It adds no new features. The only “bug” it fixes is that if you ever install net-ssh 2.x, Cap 1.4.2 will still happily continue to work.
Ultimately, an upgrade to Cap 2 is recommended, but I understand it’s not feasible for everyone. So, if you’re one of those who can’t go cap2 yet, please please please PLEASE PLEASE FOR THE LOVE OF ALL THAT IS HOLY upgrade to Cap 1.4.2. It’ll make your life easier, and it’ll make my life easier (because I won’t have to keep troubleshooting the same issues over and over). Thanks!