Hi!
As your post is pretty sparse in details, I guess you're talking about the bug in ncurses that breaks the way arrows works? (And may quit programs when you try to use the arrows, as a side effect)
I described it here: http://www.uponmyshoulder.com/blog/2010/os-x-10-6-3-broke-ncurses/
If we're talking about the same thing, I honestly think this is a bug. It doesn't match the documentation for ncurses, and actually makes no sense.
I submitted a bug report more than two weeks ago, without any answer from Apple so far.
A workaround (as suggested by Jonathan Groll) is to copy /usr/lib/libncurses.5.4.dylib and /usr/lib/libncurses.5.dylib from a 10.6.2 system. I don't really know what to think about such a libraries switch, as it might trigger other problems, but it does indeed fix this bug.