Mac will not start up.

When I start my Mac Powerbook OS 10.4.11 the screen goes Black and starts flickering this message appears. 2/17/2013

How can I fix or bypass this problem without any install/restore disc's.

dyld: Library not loaded: /usr/lib/libiconv.2.dylib

Referenced from: /bin/sh

Reason: Incompatible library version: sh requires version 7.0.0 or later, but libiconv.2.dylib provides version 5.0.0