Problem with wax framework, ios 5.1 and xcode 4

[Wendi Su]

I downloaded wax framework zip from 

https://github.com/downloads/probablycorey/wax/wax.framework.zip and I tested with a new created project. And it works fine.

But when I put it into my current existing project, and it just give me these errors.

Undefined symbols for architecture armv7:

  "__Z9wax_setupv", referenced from:

      -[CFlyingScene debug] in CFlyingScene.o

ld: symbol(s) not found for architecture armv7

clang: error: linker command failed with exit code 1 (use -v to see invocation)

And just like above, none of methods within wax.h can be used. And I check for both 2 projects, their building phase and build settings are identical. I have no idea what went wrong.