I have created a chroot jail, but now I want to be able to create a link within the jail which links outside of the jail. Is this possible?
The only method I can think of is used of a bind mount. A quick google found http://docs.1h.com/Bind_mounts
Yes, as Christopher said, a bind mount will work. But I think it will work only with directories and not at file level.
If you need file links you can use hard links but it will only work within a Linux ext filesystem (don't know if other fs support it)
See Here for a description of the difference between hard and soft links.